Article Metadata Elements



<!-- ============================================================= -->
<!--  MODULE:    Journal Article Metadata Elements                 -->
<!--  VERSION:   1.1                                               -->
<!--  DATE:      November 1, 2003                                  -->
<!--                                                               -->
<!-- ============================================================= -->

<!-- ============================================================= -->
<!--                    PUBLIC DOCUMENT TYPE DEFINITION            -->
<!--                        TYPICAL INVOCATION                     -->
<!--
"-//NLM//DTD Archiving and Interchange DTD Suite Journal Article Metadata Elements v1.1 20031101//EN"
     Delivered as file "articlemeta.ent"                           -->
<!-- ============================================================= -->

<!-- ============================================================= -->
<!-- SYSTEM:     Archiving and Interchange DTD Suite               -->
<!--                                                               -->
<!-- PURPOSE:    Names all elements used to describe the journal   -->
<!--             in which the journal article is published.        -->
<!--                                                               -->
<!-- CONTAINS:   1. Article element parameter entity               -->
<!--             2. Article metadata elements in alphabetical      -->
<!--                order                                          -->
<!--                                                               -->
<!-- CREATED FOR:                                                  -->
<!--             Digital archives and publishers who wish to       -->
<!--             create a custom XML DTD for original markup of    -->
<!--             journal literature, books, and related material,  -->
<!--             or for archiving and transferring such material   -->
<!--             between archives.                                 -->
<!--                                                               -->
<!--             This DTD is in the public domain. An organization -->
<!--             that wishes to create its own DTD from the suite  -->
<!--             may do so without permission from NLM.            -->
<!--                                                               -->
<!--             The suite has been set up to be extended using a  -->
<!--             new DTD file and a new DTD-specific customization -->
<!--             module to redefine the many Parameter Entities.   -->
<!--             Do not modify the suite directly or redistribute  -->
<!--             modified versions of the suite.                   -->
<!--                                                               -->
<!--             In the interest of maintaining consistency and    -->
<!--             clarity for potential users, NLM requests:        -->
<!--                                                               -->
<!--             1. If you create a DTD from the Archiving and     -->
<!--                Interchange DTD Suite and intend to stay       -->
<!--                compatible with the suite, then please include -->
<!--                the following statement as a comment in all of -->
<!--                your DTD modules:                              -->
<!--                   "Created from, and fully compatible with,   -->
<!--                    the Archiving and Interchange DTD Suite."  -->
<!--                                                               -->
<!--             2. If you alter one or more modules of the suite, -->
<!--                then please rename your version and all its    -->
<!--                modules to avoid any confusion with the        -->
<!--                original suite. Also, please include the       -->
<!--                following statement as a comment in all your   -->
<!--                DTD modules:                                   -->
<!--                   "Based in part on, but not fully compatible -->
<!--                    with, the Archiving and Interchange DTD    -->
<!--                    Suite."                                    -->
<!--                                                               -->
<!--             Suggestions for refinements and enhancements to   -->
<!--             the DTD suite should be sent in email to:         -->
<!--                 archive-dtd@ncbi.nlm.nih.gov                  -->
<!--                                                               -->
<!-- ORIGINAL CREATION DATE:                                       -->
<!--             December 2002                                     -->
<!--                                                               -->
<!-- CREATED BY: Jeff Beck       (NCBI)                            -->
<!--             Deborah Lapeyre (Mulberry Technologies, Inc.)     -->
<!--             Bruce Rosenblum (Inera Inc.)                      -->
<!--                                                               -->
<!--             NLM thanks the Harvard University Libraries, both -->
<!--             for proposing that a draft archiving NLM DTD for  -->
<!--             life sciences journals be extended to accommodate -->
<!--             journals in all disciplines and for sponsoring    -->
<!--             Bruce Rosenblum's collaboration with other DTD    -->
<!--             authors in completing Version 1.0. The Andrew W.  -->
<!--             Mellon Foundation provided support for these      -->
<!--             important contributions.                          -->
<!--                                                               -->
<!-- ============================================================= -->


<!-- ============================================================= -->
<!--                    DTD VERSION\CHANGE HISTORY                 -->
<!-- ============================================================= -->
<!--

     =============================================================

Version  Reason/Occasion                   (who) vx.x (yyyy-mm-dd)

     =============================================================
     Version 1.1                           (TRG) v1.1 (2003-11-01)

  3. Added element <label> to content model of element <author-notes>
     (via %author-notes-elements;)
     Rationale: To allow label as a format override

  2. Created parameter entity %author-notes-elements; to hold
     contents of <author-notes>
     Rationale: In order to distinguish between models used by
     the Archiving DTD and the Publishing DTD, it was necessary
     to create a parameter entity that could be overridden.

  1. Added parameter entity %label.class; to parameter
     %corresp-elements;
     Rationale: To allow label as a format override
                                                                   -->


<!-- ============================================================= -->
<!--                    PARAMETER ENTITY DEPENDENCIES
                        Requires the following parameter entities
                        be defined before calling this module,
                        usually accomplished in the Customization
                        Module for the specific DTD:
                                 Classes and Mixes
                        %address.elems;
                        %break.class;
                        %conference.class;
                        %contrib-info;
                        %emphasis.class;
                        %inline-display.class;
                        %inline-math;
                        %link.class;
                        %just-rendition;
                        %references.class;
                        %rendition-plus;
                        %simple-link.class;
                        %simple-phrase.class;
                        %simple-text;
                        %subsup.class;
                        %title-elements;
                                Complete Content Models
                        %article-meta-model;
                        %date-model;
                        %sec-opt-title-model;
                                 Attribute Values
                        %pub-id-types;
                                 Attribute Lists
                        %might-link-atts;
                                                                   -->
<!-- ============================================================= -->


<!-- ============================================================= -->
<!--                    PARAMETER ENTITIES FOR ATTRIBUTE VALUES    -->
<!-- ============================================================= -->


<!--                    PUBLICATION TYPES                          -->
<!--                    Used to record the type of publication, for
                        example a print-only publication versus
                        an electronic-only publication, in any of
                        several life stages.
                          This Parameter Entity is intended to name
                        the values of the "pub-type" attribute, but
                        in Version 1.0 of this DTD Suite, the
                        "pub-type" attribute is defined with a
                        Declared Value of CDATA and this Parameter
                        Entity is not used or provide its values.
                        Suggested values include:
                          epub        - Electronic publication
                          ppub        - Print publication
                          epub-ppub   - Published in both print and
                                        electronic form
                          epreprint   - Electronic preprint
                                        dissemination
                          ppreprint   - Print preprint dissemination
                          ecorrected  - Corrected in electronic
                          pcorrected  - Corrected in print
                          eretracted  - Retracted in electronic
                          pretracted  - Retracted in print         -->
<!ENTITY % pub-types      "epub | ppub | epub-ppub | epreprint |
                           ppreprint | ecorrected | pcorrected |
                           eretracted | pretracted"                  >


<!-- ============================================================= -->
<!--                    PARAMETER ENTITIES FOR ATTRIBUTE LISTS     -->
<!-- ============================================================= -->


<!--                    ABSTRACT ATTRIBUTES                        -->
<!--                    Attributes for the <abstract> element and
                        the <trans-abstract> element               -->
<!ENTITY % abstract-atts
            "abstract-type
                        CDATA                              #IMPLIED
             xml:lang   NMTOKEN                            #IMPLIED" >


<!--                    ALTERNATE TITLE ATTRIBUTES                 -->
<!--                    Attributes for the <alt-title> element     -->
<!--         alt-title-type
                        Why this title was created, for example,
                        "short" for a short version of the title,
                        "toc" for use in a Table of Contents, "ASCII"
                        for an ASCII title, "right-running" for
                        a right-running-head title, etc.           -->
<!ENTITY % alt-title-atts
            "alt-title-type
                        CDATA                              #IMPLIED" >


<!--                    CONTRIBUTOR ATTRIBUTES                     -->
<!--                    Attributes for the Contributor <contrib>
                        element                                    -->
<!--         contrib-type
                        What was the contribution of this person,
                        for example: author, editor, contributor,
                        translator, illustrator, designer,
                        research assistant, etc.
             id         Unique identifier, so the contributor can be
                        referenced
             corresp    Corresponding Author (Set to 'yes' if this
                        contributor is a corresponding author.)
             equal-contrib
                        Contributed equally (Set to 'yes' if all
                        contributors contributed equally.)
             deceased   Deceased (Set to 'yes' if the contributor
                        has died.)
             rid        May be used to point to information concerning
                        the contributor, for example to the <corresp>
                        Corresponding Information element.  There
                        is no limit to the number of contributors
                        that can be designated as corresponding.
             xlink:href Provides an address or identifier of the
                        object to which the link points, for
                        example a URI or a filename.               -->
<!ENTITY % contrib-atts
            "contrib-type
                        CDATA                              #IMPLIED
             id         ID                                 #IMPLIED
             corresp    (no | yes)                         #IMPLIED
             equal-contrib
                        (no | yes)                         #IMPLIED
             deceased   (no | yes)                         #IMPLIED
             rid        IDREFS                             #IMPLIED
             %might-link-atts;                                     " >


<!--                    KEYWORD GROUP ATTRIBUTES                   -->
<!--                    Attributes for the <kwd-group> element     -->
<!ENTITY % kwd-group-atts
            "id         ID                                 #IMPLIED
             kwd-group-type
                        CDATA                              #IMPLIED
             xml:lang   NMTOKEN                            #IMPLIED" >



<!--                    PRODUCT ATTRIBUTES                         -->
<!--                    Attributes for the Product <product>
                        element                                    -->
<!--         product-type
                        Type of product being reviewed, for example:
                        book, software package, journal or journal
                        issue, website, film, hardware component,
                        etc.
             xlink:href Provides an address or identifier of the
                        object to which the link points, for
                        example a URI or a filename                -->
<!ENTITY % product-atts
            "product-type
                        CDATA                              #IMPLIED
             %might-link-atts;"                                      >


<!--                    PUBLICATION DATE ATTRIBUTES                -->
<!--                    Attributes for the <pub-date> element      -->
<!--                    Used to record the type of publication, for
                        example a print-only publication versus
                        an electronic-only publication, in any of
                        several life stages.
                        Suggested values include:
                          epub        - Electronic publication
                          ppub        - Print publication
                          epub-ppub   - Published in both print and
                                        electronic form
                          epreprint   - Electronic preprint
                                        dissemination
                          ppreprint   - Print preprint dissemination
                          ecorrected  - Corrected in electronic
                          pcorrected  - Corrected in print
                          eretracted  - Retracted in electronic
                          pretracted  - Retracted in print
                                                                   -->
<!ENTITY % pub-date-atts
            "pub-type   CDATA                              #IMPLIED" >


<!--                    SUBJECT GROUP ATTRIBUTES                   -->
<!--                    Attributes for the <subj-group> element    -->
<!--         xml:lang   The language in which the value of the
                        element is expressed.  Recommended best
                        practice is to use values as defined in
                        RFC 1766, typically 2-letter language
                        codes such as "FR" (French), "EN" (English),
                        and "DE" (German). These values are NOT
                        case sensitive, so "EN" = "en". The values
                        may include hyphenated differentiators such
                        as "EN-AU" (Australian English) and "EN-US"
                        (United States English).
             subj-group-type
                        Identification of the subject, information
                        class, or type of this particular subject
                        group                                      -->
<!ENTITY % subj-group-atts
            "xml:lang   NMTOKEN                            #IMPLIED
             subj-group-type
                        CDATA                              #IMPLIED" >


<!--                    SUPPLEMENT ATTRIBUTES                      -->
<!--                    Attributes for the <supplement> element    -->
<!--        supplement-type
                        Indicates what sort of supplement, if the
                        for example: "issue" meaning a supplement to
                        a particular journal issue; "conference",
                        meaning the supplement contains information
                        from a conference, symposium, or other
                        gathering; "periodic" for supplements issued
                        at regular intervals, etc.                 -->
<!ENTITY % supplement-atts
            "supplement-type
                        CDATA                              #IMPLIED" >


<!-- ============================================================= -->
<!--                    PARAMETER ENTITIES FOR CONTENT MODELS      -->
<!-- ============================================================= -->


<!--                    CONTRIBUTOR INFORMATION                    -->
<!ENTITY % contrib-info "address | aff | author-comment | bio |
                         email |  ext-link | on-behalf-of |
                         role | xref"                                >


<!-- ============================================================= -->
<!--                    ARTICLE METADATA                           -->
<!-- ============================================================= -->


<!--                    ARTICLE METADATA MODEL                     -->
<!ENTITY % article-meta-model
                        "article-id*, article-categories?,
                         title-group?, (contrib-group | aff)*,
                         author-notes?, pub-date*, volume?, issue?,
                         supplement?,
                         ((fpage, lpage?) | elocation-id)?,
                         (ext-link|product|supplementary-material)*,
                         history?, copyright-statement?,
                         copyright-year?,
                         self-uri*, related-article*, abstract*,
                         trans-abstract*, kwd-group*,
                         contract-num*, contract-sponsor*,
                         conference*, counts?"                       >


<!--                    ARTICLE METADATA                           -->
<!--                    Metadata that identifies this article      -->
<!ELEMENT  article-meta (%article-meta-model;)                       >


<!--ELEM   copyright-statement
                        Defined in %common.ent"                    -->


<!-- ============================================================= -->
<!--                    ARTICLE METADATA ELEMENTS                  -->
<!-- ============================================================= -->


<!-- ============================================================= -->
<!--                    ARTICLE IDENTIFICATION                     -->
<!-- ============================================================= -->


<!--                    ARTICLE IDENTIFIER                         -->
<!--                    Optional element, used to hold one of the
                        "unique identifiers" that have been assigned
                        at various times to an article.  Such
                        identifiers may come from the publisher, the
                        jobber, or from inside PMC. Examples of such
                        numbers are the publishers tracking number,
                        the PNAS number, etc. PMC tries to carry
                        all identifiers associated with an article,
                        whether they came in as elements or attributes
                        on the original article.
                          The "type attribute" should only be used if
                        the type is known, for example, to identify
                        DOIs.                                      -->
<!ELEMENT  article-id   (#PCDATA)                                    >
<!--         pub-id-type
                        Publication (article) Identifier Type
                        Names the type of identifier, or the
                        organization or system that defined this
                        identifier for the identifier of the journal
                        article or a cited publication.
                           Used on the <article-id> element, which
                        holds an identifier for the entire article.
                           Also used on the <pubid> element, which
                        is an identifier for a publication cited in
                        a bibliographic reference (citation).
                        Valid Types include:
                          coden  - Obsolete PDB/CCDC identifier (may
                                   be present on older articles)
                          doi    - Digital Object Identifier
                          medline- NLM Medline identifier
                          other  - None of the named identifiers
                          pii    - Publisher Item Identifier, see
                                    http://pubs.acs.org/epub/piius.htm
                                   or
                                    http://www.aip.org/epub/piipr.html
                          pmid   - PUBMED ID (see
                                   www.ncbi.nlm.nih.gov/entrez/
                                   query.fcgi?db=PubMed)
                          publisher-id
                                 - Publisher's identifier such
                                   as an 'article-id', 'artnum',
                                   'identifier', 'article- number',
                                   'pub-id', etc.
                          sici   - Serial Item and Contribution
                                   Identifier (SICI). A journal
                                   article may have more than one
                                   SICI, one for a print version and
                                   one for an electronic version.  -->
<!ATTLIST  article-id
             pub-id-type
                        (%pub-id-types;)                   #IMPLIED  >


<!-- ============================================================= -->
<!--                    ARTICLE GROUPING DATA (ARTICLE METADATA)   -->
<!-- ============================================================= -->


<!--                    ARTICLE GROUPING DATA                      -->
<!--                    Container for elements that may be used to
                        group articles into related clusters       -->
<!ELEMENT  article-categories
                        (subj-group*, series-title*, series-text?)   >


<!--                    GROUPING ARTICLES IN TITLED CATEGORIES
                        For some journals, articles are grouped into
                        categories, with the category indicated in
                        the article's display.
                        Sometimes the grouping or category refers
                        to the type of article, such as "Essay",
                        "Commentary", or "Article".  Sometimes the
                        grouping refers to subject areas, such as
                        "Physical Sciences", "Biological Sciences",
                        or "Social Sciences". Sometimes the grouping
                        refers to topics within the larger subject
                        areas, such as "Applied Math", "Biology", or
                        "Chemistry".

                        In a printed journal as well as on the PMC
                        website, articles may be grouped or arranged
                        under these headings (here are all the
                        Essays, here are all the Biology articles,
                        etc.) Some journals divide articles into
                        three layers of grouping, some into two, and
                        some into only one.
                        For example, a three level grouping might be:
                         <subj-group>
                           <subject>Articles</subject>
                           <subj-group>
                             <subject>Biological Sciences</subject>
                             <subj-group>
                               <subject>Entomology</subject>
                             </subj-group>
                           </subj-group>
                         </subj-group>
                        And a one-level grouping might be
                         <subj-group>
                          <subject>Retraction</subject>
                         </subj-group>
                        or, alternatively
                         <subj-group>
                          <subject>Essay</subject>
                         </subj-group>

                        Articles may also be assigned to more than
                        one grouping. For example, if an article is
                        classified as "Biochemistry" under
                        "Biological Sciences" and "Chemistry" under
                        "Physical Sciences," the subj-group wrapper
                        may repeat.

                        For example,
                         <subj-group>
                           <subject>Articles</subject>
                           <subj-group>
                             <subject>Biological Sciences</subject>
                             <subj-group>
                               <subject>Biochemistry</subject>
                             </subj-group>
                           </subj-group>
                           <subj-group>
                             <subject>Physical Sciences</subject>
                             <subj-group>
                                <subject>Chemistry</subject>
                             </subj-group>
                         </subj-group>
                                                                   -->
<!ELEMENT  subj-group   (subject+, subj-group*)                      >
<!--         xml:lang   The language in which the value of the
                        element is expressed.  Recommended best
                        practice is to use values as defined in
                        RFC 1766, typically 2-letter language
                        codes such as "FR" (French), "EN" (English),
                        and "DE" (German). These values are NOT
                        case sensitive, so "EN" = "en". The values
                        may include hyphenated differentiators such
                        as "EN-AU" (Australian English) and "EN-US"
                        (United States English).
             subj-group-type
                        Identification of the subject, information
                        class, or type of this particular subject
                        group                                      -->
<!ATTLIST  subj-group
             %subj-group-atts;                                       >


<!--                    SUBJECT GROUPING NAME ELEMENTS             -->
<!--                    Elements that may be used, along with data
                        characters inside the content model of the
                        <subject> element                          -->
<!ENTITY % subject-elements
                        "| %emphasis.class; | %inline-display.class; |
                        %inline-math; | %subsup.class;"              >


<!--                    SUBJECT GROUPING NAME                      -->
<!--                    The name of one of the subject groups used
                        to describe an article.  Such groups are
                        used, typically, to provide headings for
                        groups of articles in a printed or online
                        generated Table of Contents.               -->
<!ELEMENT  subject      (#PCDATA %subject-elements;)*                >


<!-- ============================================================= -->
<!--                    SERIES INFORMATION                         -->
<!-- ============================================================= -->

<!--                    GROUPING ARTICLES IN SERIES
                        Series (as used in the <series-title> and
                        <series-text> elements described below) is
                        used in two different senses. Some issues of
                        journals are part of a series and will have
                        series information just as they have an
                        issue number as part of the article metadata,
                        to describe the issue of the journal in which
                        the article is published.  The second usage
                        is for groupings of articles within one
                        issue of a journal. For example, in some
                        journals, articles are grouped into a
                        series such as "From the Cover" and
                        identified as part of a series.
                        The Series Title element names the series
                        and the Series Text element provides textual
                        description (if any) describing the series.-->


<!--                    SERIES TITLE                               -->
<!--                    Title of the journal series (bibliographic
                        meaning) or the title of a  series of
                        articles internal to one issue of a journal
                                                                   -->
<!ELEMENT  series-title (#PCDATA %rendition-plus;)*                  >


<!--                    SERIES TEXT: HEADER TEXT to DESCRIBE       -->
<!--                    Textual description of the series of articles
                        that are named in a <series-title> element -->
<!ELEMENT  series-text  (#PCDATA %rendition-plus;)*                  >


<!-- ============================================================= -->
<!--                    TOP-LEVEL ARTICLE METADATA CONTINUED       -->
<!-- ============================================================= -->


<!--                    AUTHOR NOTE GROUP ELEMENTS                 -->
<!--                    The elements that can be included inside
                        the content model of a <author-notes>.     -->
<!ENTITY % author-notes-elements
                        "label?, title?, (corresp | fn)+"            >


<!--                    AUTHOR NOTE GROUP                          -->
<!--                    Footnotes to authors or notes about authors
                        (and, potentially other contributors) are
                        collected in the Author note group.
                        References to these footnotes are made
                        using the <xref> element.
                        Authoring Note:  While this element
                        contains an optional Label element, the
                        Label element should be included only in
                        those circumstances where a formatting
                        override is needed; Label should NOT
                        be used in the ordinary course of
                        tagging.                                   -->
<!ELEMENT  author-notes (%author-notes-elements;)                    >
<!--         id         Unique identifier so that the note group
                        may be referenced, for example by an author
             rid        May be used to point to an author, if the
                        source has recorded connections in both
                        directions                                 -->
<!ATTLIST  author-notes
             id         ID                                 #IMPLIED
             rid        IDREFS                             #IMPLIED  >


<!--ELEM   volume       Defined in %common.ent;                    -->
<!--ELEM   issue        Defined in %common.ent;                    -->
<!--ELEM   supplement   Defined in %common.ent;                    -->
<!--ELEM   fpage        Defined in %common.ent;                    -->
<!--ELEM   lpage        Defined in %common.ent;                    -->
<!--ELEM   elocation-id Defined in %common.ent;                    -->
<!--ELEM   ext-link     Defined in %common.ent;                    -->
<!--ELEM   lpage        Defined in %common.ent;                    -->


<!-- ============================================================= -->
<!--                 PRODUCT REVIEW INFORMATION (PRODUCT METADATA) -->
<!-- ============================================================= -->


<!--                    PRODUCT ELEMENTS                           -->
<!--                    Elements that may be used inside the
                        <product> element                          -->
<!ENTITY % product-elements
                        "| %break.class; | %link.class; |
                         %references.class; |  %simple-text;"        >


<!--                    PRODUCT INFORMATION                        -->
<!--                    Used as a wrapper for metadata for a product
                        (such as a book, software package, hardware
                        component, website etc.) that is being
                        reviewed.
                        Authoring and Conversion Note: This element
                        should be used when the value of the
                        "article-type" attribute on the element
                        <article> is "book-review" or
                        "product-review".

                        Authoring and Conversion Note: A review of
                        a book, journal, website, etc. should
                        include as much information about the item
                        being reviewed as is practical, for example:
                        <product>
                            <name>
                              <surname>Lapeyre</surname>
                              <given-names>Deborah A.</given-names>
                            </name>
                            <name>
                              <surname>Usdin</surname>
                              <given-names>B. Tommie</given-names>
                            </name>
                            <source>Wildflowers of the
                            Washington Area</source>
                            <year>2002</year>
                            <publisher-name>Lippman Ltd.
                            </publisher-name>
                            <publisher-loc>Bethesda, MD
                            </publisher-loc>
                            <isbn>0-23-8675-309</isbn>,
                            includes a CD-ROM,
                            <bold>$19.95</bold> (Used 12.50 when
                            available)
                         </product>
                                                                   -->
<!ELEMENT  product      (#PCDATA %product-elements;)*                >
<!--         product-type
                        Type of product being reviewed, for example:
                        book, software package, journal or journal
                        issue, website, film, hardware component,
                        etc.
              xlink:href Provides an address or identifier of the
                        object to which the link points, for
                        example a URI or a filename                -->
<!ATTLIST  product
             %product-atts;                                          >


<!-- ============================================================= -->
<!--                    PUBLICATION HISTORY ELEMENTS               -->
<!-- ============================================================= -->


<!--                    HISTORY:  DOCUMENT HISTORY                 -->
<!--                    Used as a container for dates related to the
                        processing history of the document, such as
                        received date and accepted date.
                        Authoring and Conversion Note: The dates
                        inside the <history> element are used to
                        preserve events other than publication dates
                        in the lifecycle of the article. Publication
                        dates are considered to be an important
                        part of the metadata. History dates include
                        accepted date, received date, reviewed
                        date, and other dates that may be important
                        to the publisher but are not a likely part
                        of the article metadata for searching,
                        building a DOI, etc.                       -->
<!ELEMENT  history      (date+)                                      >


<!-- ============================================================= -->
<!--                    FURTHER METADATA ELEMENTS                  -->
<!-- ============================================================= -->


<!--                    COPYRIGHT YEAR                             -->
<!--                    Year of the copyright. Need not be used, if,
                        for example, having the year as part of the
                        copyright statement is sufficient.
                        Note: since Copyright Statement is intended
                        for display, Copyright Year is not expected
                        to be displayed (but will be available for
                        searching).                                -->
<!ELEMENT  copyright-year
                        (#PCDATA)                                    >


<!--                    URI FOR THIS SAME ARTICLE ONLINE           -->
<!--                    Sometimes an article is available in several
                        forms, for example there is the version that
                        was published in print and there is the same
                        article (possibly expanded or with different
                        graphics) available online.
                           The URI (such as a URL) may be used as a
                        live link, typically naming a website or the
                        element content may name the URL, e.g., and
                        use the link attributes to hold the real link:
                           <self-uri xlink:href="...">An expanded
                           version of this article is available
                           online</self-uri>                       -->
<!ELEMENT  self-uri     (#PCDATA)                                    >
<!ATTLIST  self-uri
             %might-link-atts;                                       >


<!--ELEM   related-article
                        Defined in %common.ent;                    -->


<!-- ============================================================= -->
<!--                    ABSTRACTS                                  -->
<!-- ============================================================= -->


<!--                    ABSTRACT MODEL                             -->
<!--                    Content model for an <abstract> element    -->
<!ENTITY % abstract-model
                        "%sec-opt-title-model;"                      >


<!--                    ABSTRACT                                   -->
<!ELEMENT  abstract     (%abstract-model;)                           >
<!--         abstract-type
                        What type of abstract, for the various
                        styles of abstracts that publishers
                        identify, such as:
                          ASCII        Without special characters or
                                       equations so it can be sent in
                                       email or displayed on primitive
                                       browsers
                           executive-summary
                                       A non-technical summation of
                                       the major findings of the
                                       article
                           graphical   The abstract is a picture
                           editor      For an abstract written by an
                                       editor and not the author
                           key-points  An abstract which is a list of
                                       the key points made by the
                                       document
                           objectives  Used for Learning Objectives
                                       or article objectives
                           short       An abbreviated form of the
                                       abstract, for use, for example
                                       inside a generated Table of
                                       Contents, or to be returned
                                       in addition to the article
                                       title during a search
                           stereochemical
                                       An abstract containing only
                                       the details of a chemical
                                       compound (For example, the
                                       Elsevier DTD "stereochem"
                           summary     Summation of the article,
                                       typically used in conjunction
                                       with other types of abstracts
                           teaser      A short abstract specifically
                                       written to draw the attention
                                       of the reader
                           toc         A line or two that displays
                                       in a table of contents
                           web-summary
                                       Short summary intended for
                                       distribution on a website   -->
<!ATTLIST  abstract
             %abstract-atts;                                         >


<!--                    TRANSLATED ABSTRACT MODEL                  -->
<!--                    Content model for an <trans-abstract> element
                                                                   -->
<!ENTITY % trans-abstract-model
                        "%sec-opt-title-model;"                      >


<!--                    TRANSLATED ABSTRACT                        -->
<!--                    An abstract that has been translated into
                        another language                           -->
<!ELEMENT  trans-abstract
                        (%trans-abstract-model;)                     >
<!--         abstract-type
                        What type of abstract, for the various
                        unusual styles of abstracts that publishers
                        identify, such as "short" abstract, "graphic"
                        abstract, "ASCII" abstract, "stereochemical"
                        abstract, etc.
             xml:lang   The language in which the value of the
                        element is expressed.  Recommended best
                        practice is to use values as defined in
                        RFC 1766, typically 2-letter language
                        codes such as "FR" (French), "EN" (English),
                        and "DE" (German). These values are NOT
                        case sensitive, so "EN" = "en". The values
                        may include hyphenated differentiators such
                        as "EN-AU" (Australian English) and "EN-US"
                        (United States English).                   -->
<!ATTLIST  trans-abstract
             %abstract-atts;                                         >


<!-- ============================================================= -->
<!--                    KEYWORD ELEMENTS                           -->
<!-- ============================================================= -->


<!--                    KEYWORD GROUP                              -->
<!--                    Container element for one set of keywords
                        used to describe a document.
                        Remarks: A document may have multiple sets
                        of keywords, each with a source named in
                        the "kwd-group-type" attribute.            -->
<!ELEMENT  kwd-group    (title?, kwd+)                               >
<!--         id         Unique identifier so the element may be
                        referenced
             kwd-group-type
                        Name of the source of the keywords, for
                        example "MESH", "IEEE", "author",
                        "ICD9-codes", etc.
             xml:lang   The language in which the value of the
                        element is expressed.  Recommended best
                        practice is to use values as defined in
                        RFC 1766, typically 2-letter language
                        codes such as "FR" (French), "EN" (English),
                        and "DE" (German).  These values are NOT
                        case sensitive, so "EN" = "en". The values
                        may include hyphenated differentiators such
                        as "EN-AU" (Australian English) and "EN-US"
                        (United States English).                   -->
<!ATTLIST  kwd-group
             %kwd-group-atts;                                        >


<!--ELEM   title        Defined in %common.ent;                    -->


<!--                    KEYWORD CONTENT ELEMENTS                   -->
<!--                    The elements that can be included along with
                        data characters inside the content model of
                        a keyword.                                 -->
<!ENTITY % kwd-elements
                        "| %emphasis.class; | %inline-display.class; |
                         %inline-math; | %simple-link.class; |
                         %subsup.class;"                             >


<!--                    KEYWORD                                    -->
<!--                    One subject term, critical expression, key
                        phrase, abbreviation, indexing word, etc.
                        that is associated with the whole document
                        and can be used for identification and
                        indexing purposes.
                        There maybe several sets of keywords,
                        identified by language or vocabulary source
                        at the Keyword Group level <kwd-group>.
                        Conversion Note: Keywords are not allowed to
                        nest.  There are a few journal DTDs in which
                        keyword nesting is used to simulate a two-
                        part list.  These keyword list should be
                        tagged as definition lists instead.        -->
<!ELEMENT  kwd          (#PCDATA %kwd-elements;)*                    >
<!--         id         Unique identifier so the element may be
                        referenced                                 -->
<!ATTLIST  kwd
             id         ID                                 #IMPLIED  >


<!-- ============================================================= -->
<!--                    STILL FURTHER ARTICLE METADATA             -->
<!-- ============================================================= -->


<!--                    CORRESPONDENCE INFORMATION ELEMENTS        -->
<!--                    The elements that can be included along with
                        data characters inside the content model of
                        the correspondence information.            -->
<!ENTITY % corresp-elements
                        "| %address-elements; | %emphasis.class; |
                         %label.class; | %subsup.class;"             >


<!--                    CORRESPONDENCE INFORMATION                 -->
<!--                    Optional element, used as a container for
                        information concerning which of the authors
                        (or other contributors) is the corresponding
                        contributor, to whom information requests
                        should be addressed.
                        A cross-reference element may point to the
                        identifier attribute.
                        Authoring Note:  While this element
                        contains an optional Label element, the
                        Label element should be included only in
                        those circumstances where a formatting
                        override is needed; Label should NOT
                        be used in the ordinary course of
                        tagging.                                   -->
<!ELEMENT  corresp      (#PCDATA %corresp-elements;)*                >
<!--         id         Unique identifier, so the element can be
                        referenced                                 -->
<!ATTLIST  corresp
             id         ID                                 #IMPLIED  >


<!--                    PUBLICATION DATE                           -->
<!--                    Date of publication or release of the
                        material in one particular format.  Inside
                        the article metadata, the Publication Date
                        is allowed to repeat, and each date can take
                        a "pub-type" attribute to distinguish
                        which form of release or publication.      -->
<!ELEMENT  pub-date     (%date-model;)                               >
<!--                    Used to record the type of publication, that
                        was released or published on this date, for
                        example a print-only publication versus
                        an electronic-only publication, in any of
                        several life stages.
                        Suggested values include:
                          epub        - Electronic publication
                          ppub        - Print publication
                          epub-ppub   - Published in both print and
                                        electronic form
                          epreprint   - Electronic preprint
                                        dissemination
                          ppreprint   - Print preprint dissemination
                          ecorrected  - Corrected in electronic
                          pcorrected  - Corrected in print
                          eretracted  - Retracted in electronic
                          pretracted  - Retracted in print         -->
<!ATTLIST  pub-date
             %pub-date-atts;                                         >


<!-- ============================================================= -->
<!--                    CONTRACT/GRANT INFORMATION ELEMENTS        -->
<!-- ============================================================= -->


<!--                    CONTRACT/GRANT NUMBER ELEMENTS             -->
<!--                    The elements that can be included along with
                        data characters inside the content model of
                        the contract number.                       -->
<!ENTITY % contract-elements "| %simple-text;"                       >


<!--                    CONTRACT/GRANT NUMBER                      -->
<!--                    Contract or grant number of the supported
                        work described in the article.
                        Authoring Conversion Note: If an acronym of
                        the sponsor is available, it should be
                        inserted before the number.                -->
<!ELEMENT  contract-num
                        (#PCDATA %contract-elements;)*               >


<!--                    CONTRACT/GRANT SPONSOR ELEMENTS            -->
<!--                    The elements that can be included along with
                        data characters inside the content model of
                        the contract sponsor.                      -->
<!ENTITY % contract-sponsor-elements
                        "| %simple-text;"                            >


<!--                    CONTRACT/GRANT SPONSOR                     -->
<!--                    Name of the organization that sponsored the
                        work described in the article.
                        proceedings.                               -->
<!ELEMENT  contract-sponsor
                        (#PCDATA %contract-sponsor-elements;)*       >


<!-- ============================================================= -->
<!--                    CONFERENCE INFORMATION ELEMENTS            -->
<!-- ============================================================= -->


<!--                    CONFERENCE MODEL                           -->
<!ENTITY % conference-model
                        "(%conference.class;)*"                      >


<!--                    CONFERENCE INFORMATION                     -->
<!--                    The container element for the information
                        about a single conference and its
                        proceedings.
                        Design Note: Conference elements were largely
                        based on Cross-Ref.                        -->
<!ELEMENT  conference   %conference-model;                           >


<!--ELEM   conf-date     Defined in %common.ent;                   -->
<!--ELEM   conf-name     Defined in %common.ent;                   -->


<!--                    CONFERENCE NUMBER ELEMENTS                 -->
<!--                    The elements that can be included along with
                        data characters inside the content model of
                        the conference number.                     -->
<!ENTITY % conf-num-elements
                        "| %simple-text;"                            >


<!--                    CONFERENCE NUMBER                          -->
<!--                    The sequential number of the conference.
                        Authoring and Conversion Note: Ideally, the
                        conference number should include only the
                        numeric portion of the number without any
                        suffixes or other text. For example, "The
                        19th XML/SGML Conference" should be tagged as
                           <conf-num>19</conf-num>
                        with the "th" dropped.                     -->
<!ELEMENT  conf-num     (#PCDATA %conf-num-elements;)*               >


<!--                    CONFERENCE SPONSOR  ELEMENTS               -->
<!--                    The elements that can be included along with
                        data characters inside the content model of
                        the conference sponsor.                    -->
<!ENTITY % conf-sponsor-elements
                        "| %simple-text;"                            >


<!--                    CONFERENCE SPONSOR                         -->
<!--                    One organization that sponsored the
                        conference. If more than one organization
                        sponsored the conference, multiple
                        <conf-sponsor> elements should be used.    -->
<!ELEMENT  conf-sponsor (#PCDATA %conf-sponsor-elements;)*           >


<!--                    CONFERENCE THEME ELEMENTS                  -->
<!--                    The elements that can be included along with
                        data characters inside the content model of
                        the conference theme.                      -->
<!ENTITY % conf-theme-elements
                        "| %simple-text;"                            >


<!--                    CONFERENCE THEME                           -->
<!--                    The theme, slogan, or major subject area of
                        the conference.  For example, the name of an
                        annual conference, may be "16th ACH Gathering"
                        but each year has a different theme topic,
                        such as "Database Integration" or "Topic
                        Map Subject Access".                       -->
<!ELEMENT  conf-theme   (#PCDATA %conf-theme-elements;)*             >


<!--                    CONFERENCE ACRONYM ELEMENTS                -->
<!--                    The elements that can be included along with
                        data characters inside the content model of
                        the conference acronym.                    -->
<!ENTITY % conf-acronym-elements
                        "| %simple-text;"                            >


<!--                    CONFERENCE ACRONYM                         -->
<!--                    The short name, popular name, or "jargon
                        name" for a conference, for example,
                        "Extreme" for "Extreme Markup Languages" or
                        "SIGGRAPH" for "Special Interest Group on
                        Computer Graphics". Provided for searching
                        convenience when the jargon name is better
                        known that the full formal conference name.
                          Authoring and Conversion Note: A conference
                        acronym often includes the year of the
                        conference (e.g. "SGML '97") or, less often,
                        the conference number (e.g., "AMBA 6"). It
                        is preferred, but not required, that the
                        acronym exclude this year or number (thus
                        using "SGML" or "AMBA" and putting the year
                        or number in the <conf-date> and
                        <conf-num> elements, respectively.         -->
<!ELEMENT  conf-acronym (#PCDATA %conf-acronym-elements;)*           >


<!-- ============================================================= -->
<!--                    COUNTING INFORMATION (ARTICLE METADATA)    -->
<!-- ============================================================= -->


<!ENTITY % counts-model "fig-count?, table-count?, equation-count?,
                         ref-count?, page-count?, word-count?"       >


<!--                    COUNTS                                     -->
<!--                    Wrapper element to hold all metadata that
                        "counts how many of something appear in the
                        article                                    -->
<!ELEMENT  counts       (%counts-model;)                             >


<!--                     EQUATION COUNT                            -->
<!--                     Number of display equations <disp-formula>
                         that appear in the article. Inline-equations
                         <inline-formula> are not counted. No
                         distinction is made between numbered and
                         unnumbered equations, both are counted.   -->
<!ELEMENT  equation-count
                         EMPTY                                       >
<!--                     The "count" attribute indicates the number
                         of display equations <disp-formula> in the
                         article. Inline-equations <inline-formula>
                         are not counted. No distinction is made
                         between numbered and unnumbered equations,
                         both are counted.                         -->
<!ATTLIST  equation-count
            count        NMTOKEN                           #REQUIRED >


<!--                     FIGURE COUNT                              -->
<!--                     Number of Figures <fig> that appear in the
                         article. Loose <graphic>s that appear
                         outside figures are not counted.          -->
<!ELEMENT  fig-count     EMPTY                                       >
<!--                     The "count" attribute indicates the number
                         of figures in the article, that is, how
                         many <fig> elements are used              -->
<!ATTLIST  fig-count
            count        NMTOKEN                           #REQUIRED >


<!--                     TABLE COUNT                               -->
<!--                     Number of tables (Table Wrapper <table-wrap>
                         elements that appear in the article. Arrays
                         are not counted as tables.                -->
<!ELEMENT  table-count   EMPTY                                       >
<!--                     The "count" attribute indicates the number
                         of tables in the article, that is, how
                         many <table-wrap> elements are used.      -->
<!ATTLIST  table-count
            count        NMTOKEN                           #REQUIRED >


<!--                     REFERENCE COUNT                           -->
<!--                     Number of reference citations <citation>
                         that appear in the bibliographic reference
                         list <ref-list> in the article            -->
<!ELEMENT  ref-count     EMPTY                                       >
<!--                     The "count" attribute indicates the number
                         of reference citations in the article     -->
<!ATTLIST  ref-count
            count        NMTOKEN                           #REQUIRED >


<!--                     PAGE COUNT                                -->
<!--                     Number of pages in a print article, counting
                         each page or partial page as one. Electronic
                         articles do not have page counts.         -->
<!ELEMENT  page-count    EMPTY                                       >
<!--                     The "count" attribute indicates the number
                         of pages in the article                   -->
<!ATTLIST  page-count
            count        NMTOKEN                           #REQUIRED >


<!--                     WORD COUNT                                -->
<!--                     Approximate number of words that appear in
                         the article                               -->
<!ELEMENT  word-count    EMPTY                                       >
<!--                     The "count" attribute indicates the number
                         of  words in the textual portion of an
                         article (not including the words in the
                         metadata or header information)           -->
<!ATTLIST  word-count
            count        NMTOKEN                           #REQUIRED >



<!-- ============================================================= -->
<!--                    TITLE GROUP ELEMENTS (BIBLIOGRAPHIC)       -->
<!-- ============================================================= -->


<!--                    TITLE GROUP MODEL                          -->
<!--                    Content model for the <title-group> element-->
<!ENTITY % title-group-model
                        "article-title, subtitle*, trans-title*,
                         alt-title*, fn-group?"                      >


<!--                    TITLE GROUP                                -->
<!--                    Wrapper element to hold the various article
                        titles.
                        Authoring and Conversion Note: A footnote or
                        other reference inside a title should usually
                        be placed inside the title, but may be tagged
                        in a group at the end of the <title-group>,
                        if that is the way they are in the source.)-->
<!ELEMENT  title-group  (%title-group-model;)                        >


<!--ELEM   article-title
                        Defined in %common.ent;                    -->
<!--ELEM   trans-title  Defined in %common.ent;                    -->
<!--ENTITY %title-elements;
                        Defined in %common.ent;                    -->


<!--                    ARTICLE SUBTITLE                           -->
<!ELEMENT  subtitle     (#PCDATA %title-elements;)*                  >


<!--                    ALTERNATE TITLE                            -->
<!--                    A "different" version of an article title,
                        usually created so that it can be processed
                        in a special way, for example a short
                        version of the title for use in a Table of
                        Contents, an ASCII title, a right-running-
                        head title, etc.
                        Authoring and Conversion Note: This element
                        should not be used for either the translated
                        title (which is an alternate version of a
                        title in another language) or the subtitle
                        (which is an addition to the title).       -->
<!ELEMENT  alt-title    (#PCDATA %title-elements;)*                  >
<!--         alt-title-type
                        Why this title was created, for example,
                        "short" for a short version of the title,
                        "toc" for use in a Table of Contents, "ASCII"
                        for an ASCII title, "right-running" for
                        a right-running-head title, etc.           -->
<!ATTLIST  alt-title
             %alt-title-atts;                                        >


<!-- ============================================================= -->
<!--                    CONTRIBUTOR GROUP (AUTHOR/EDITOR) ELEMENTS -->
<!-- ============================================================= -->


<!--                    CONTRIBUTOR GROUP MODEL                    -->
<!--                    Content model for the <title-group> element-->
<!ENTITY % contrib-group-model
                        "contrib+, etal?, (%contrib-info;)*"         >


<!--                    CONTRIBUTOR GROUP                          -->
<!--                    Wrapper element for information concerning
                        a grouping of contributors, such as primary
                        authors                                    -->
<!ELEMENT  contrib-group
                        (%contrib-group-model;)                      >


<!--                    CONTRIBUTOR                                -->
<!--                    Wrapper element to contain the information
                        about a single contributor, for example an
                        author or editor.
                        Authoring and Conversion Note: Use <xref>
                        to point to the institution <aff>, the
                        corresponding information <corresp>, and
                        any author footnotes in the author note
                        group.
                        Conversion Note: When the ranking or
                        importance of authors is marked as a note,
                        (for example, the ranking element in the
                        Elsevier DTD), it should be encoded in the
                        role element. Thus, the Elsevier-tagged
                        text:
                          <ranking><sup>*</sup></ranking>
                        would be converted to:
                          <role><sup>*</sup></role>
                                                                   -->
<!ELEMENT  contrib      ( (collab | (name, degrees*) )*,
                          (%contrib-info;)* )                        >
<!--         contrib-type
                        What was the contribution of this person,
                        for example: author, editor, contributor,
                        translator, illustrator, designer,
                        research assistant, etc.
             id         Unique identifier, so the contributor can be
                        referenced
             corresp    Corresponding Author (Set to 'yes' if this
                        contributor is a corresponding author.)
             equal-contrib
                        Contributed equally (Set to 'yes' if all
                        contributors contributed equally.)
             deceased   Deceased (Set to 'yes' if the contributor
                        has died.)
             rid        May be used to point to information concerning
                        the contributor, for example to the <corresp>
                        Corresponding Information element.  There
                        is no limit to the number of contributors
                        that can be designated as corresponding.
             xlink:href Provides an address or identifier of the
                        object to which the link points, for
                        example a URI or a filename.               -->
<!ATTLIST  contrib
             %contrib-atts;                                          >



<!--ELEM  collab        Defined %common.ent; (also used in
                        bibliographic citations)                   -->
<!--ELEM  etal          Defined %common.ent; (also used in
                        bibliographic citations)                   -->

<!--                    DEGREE(S)                                  -->
<!--                    Academic degrees or professional
                        certifications                             -->
<!ELEMENT  degrees      (#PCDATA %just-rendition;)*                  >


<!--                    ON BEHALF OF                               -->
<!--                    When a contributor has written or edited
                        a work  "on-behalf-of" an organization or
                        group the contributor is acting as a
                        representative of the organization, which
                        may or may not be his/her usual affiliation.
                        Related elements: Some DTDs identify this
                        category as a "collaboration", but it
                        is really more akin to a "role" the person
                        is playing with respect to the organization.
                        Thus this element joins the related
                        element <role> in describing the contribution
                        of a contributor. The <role> element will
                        say that a person is an "Editor" or
                        "Associate Editor" and the <on-behalf-of>
                        element will state that this editing was
                        undertaken as a representative of a group
                        or organization:
                        <contrib>
                             <name>
                               <surname>Campion</surname>
                               <given-names>M</given-names>
                             </name>
                             <on-behalf-of>for
                             the Multiple Sclerosis Collaborative
                             Research Group</on-behalf-of>
                          </contrib>
                           Conversion Note: In some DTDs, the
                        association "on-behalf-of" may have been
                        tagged as a <role> rather than as a
                        specific <on-behalf-of>.
                        It is therefore also acceptable although
                        not as accurate) to tag the example as:
                           <contrib>
                             <name>
                               <surname>Campion</surname>
                               <given-names>M</given-names>
                             </name>
                             <role>for the Multiple
                             Sclerosis Collaborative Research
                             Group</role>
                           </contrib>                              -->
<!ELEMENT  on-behalf-of
                        (#PCDATA %rendition-plus;)*                  >

<!--                    ROLE OR FUNCTION TITLE OF CONTRIBUTOR      -->
<!--                    A title or the role of a contributor
                        (such as an author) in this work. For example,
                        Editor-in-Chief, Contributor, Chief
                        Scientist, Photographer, Research Associate,
                        etc.
                        Remarks: Information on the role or type of
                        contribution is collected in two places,
                        in the "contrib-type" attribute on the
                        Contributor element and in the Role element.
                        For example, the Contributor attribute might
                        have a value of "editor", while the content
                        of the role element could be "Associate
                        Editor". As another example, the contributor
                        attribute might be "author" and the role
                        element might be "Principle Author".
                        The <role> element is also more likely to
                        appear on screen or in print than the
                        contributor attribute value.               -->
<!ELEMENT  role         (#PCDATA %rendition-plus;)*                  >


<!--                    AUTHOR COMMENT                             -->
<!--                    Used for extra textual material associated
                        with a contributor such as an author or
                        editor
                        Conversion Note: During conversion, this
                        element can act as an escape mechanism, to
                        hold material not anticipated by the DTD.
                                                                   -->
<!ELEMENT  author-comment
                        (title?, p+)                                 >



<!-- ============================================================= -->
<!--                    SUPPLEMENT ELEMENTS                        -->
<!-- ============================================================= -->


<!--                    SUPPLEMENT ELEMENTS                        -->
<!--                    Elements for use in the <supplement> element
                                                                   -->
<!ENTITY % supplement-elements
                        "| %simple-text;"                            >


<!--                    SUPPLEMENT                                 -->
<!--                    For a journal published as a supplement, this
                        is a container element for all the provided
                        supplement information, such as additional
                        identification numbers, titles, and
                        supplement series information.             -->
<!ELEMENT supplement    (#PCDATA %supplement-elements;)*             >
<!--        supplement-type
                        Indicates what sort of supplement, if the
                        publisher has recorded that information,
                        for example: "issue" meaning a supplement to
                        a particular journal issue; "conference",
                        meaning the supplement contains information
                        from a conference, symposium, or other
                        gathering; "periodic" for supplements issued
                        at regular intervals, etc.                 -->
<!ATTLIST supplement
            %supplement-atts;                                        >


<!-- ================== End Article Metadata Elements  =========== -->