Supplementary Material


Additional data files that contain information directly supportive of a document, for example, an audio clip, movie, database, spreadsheet, applet, or other external file

This element has a similar function to the <audiovisual> element in some XML tag sets and the <unprinted-item> element (used only for electronic files) in other tag sets.


The element is used in two senses: first, inside the metadata for a book component (<book-part>) as an alert to the existence of supplementary material; and second, as part of the textual flow, where it is similar to a <fig>, in that it can be positioned as a floating or anchored object and may take a caption.

For the second usage, the position attribute may be used to indicate whether this element must be anchored at its exact location within the text or whether it may float, for example, to the top of the next page, into the next column, to the end of a logical file, or within a separate window. The mimetype attribute may be used to identify a file type for a <supplementary-material> element.

Conversion Note: <supplementary-material> may contain a preview image (e.g., the first frame of a movie, tagged as a <graphic> or <media>), with the caption/preview placed in a manner similar to a <fig> and a cross-reference made to the material from the text.


alternate-form-of Alternate Form of Graphic, Media Object, Etc.
content-type Type of Content
id Identifier
mime-subtype Mime Subtype
mimetype Mime Type
position Position
xlink:actuate Actuating the Link
xlink:href Href (Linking Mechanism)
xlink:role Role of the Link
xlink:show Showing the Link
xlink:title Title of the Link
xlink:type Type of Link
xml:lang Language
xmlns:xlink XLink Namespace Declaration

Related Elements

This DTD Suite contains several elements to describe non-XML material: <graphic>, <inline-graphic>, <media>, <supplementary-material>, and <inline-supplementary-material>. The elements <graphic> and <inline-graphic> are used for “still” images, i.e., photographs, diagrams, etc. The distinction between the other elements is more subtle. The element <media> should be used for movies, audio clips, or media in other formats which are intrinsic to the document’s content, that is, the media object is discussed within the document. The elements <supplementary-material> and <inline-supplementary-material> should be used for films, audio clips, or other material which enhances a document, but which is not discussed as part of the document.

Use <inline-supplementary-material> to mark up text references to supplementary material where the reference appears in the regular flow of the text and does not have a preview image or separate caption. Conversely, use <supplementary-material> for a more complicated reference, where the supplementary material resembles a figure in that it can be positioned as a floating or anchored object and may take a caption.

Model Information

Content Model

<!ELEMENT  supplementary-material
                        %supplementary-material-model;               >


The following, in order:

This element may be contained in:

<abstract> Abstract; <ack> Acknowledgments; <app> Appendix; <app-group> Appendix Matter; <body> Body of the Book; <book-part-meta> Book Part Metadata; <boxed-text> Boxed Text; <disp-quote> Quote, Displayed; <gloss-group> Glossary Group; <glossary> Glossary Elements List; <named-content> Named Special (Subject) Content; <notes> Notes; <p> Paragraph; <ref-list> Reference List (Bibliographic); <sec> Section; <trans-abstract> Translated Abstract

Tagged Example

<p>The molecular determinants of transcription-complex stability 
and processivity are understood poorly. Several competing 
mechanistic models of RNAP function have been proposed ...</p>
<supplementary-material id="S1" 
<label>Additional material</label>
<p>Supplementary PDF file supplied by authors.</p>
<p>RNAPs seem to have arisen twice in evolution (see the 
xlink:title="local_file" xlink:href="timeline">Timeline
</inline-supplementary-material>. A large family of multisubunit 
RNAPs includes bacterial enzymes, archeal enzymes, eukaryotic 
nuclear RNAPs, plastid-encoded chloroplast RNAPs, and RNAPs 
from some eukaryotic viruses. Members of this family exhibit 
extensive sequence and structural similarities ...</p>