Subordinate heading or title for a book or for one of its structural elements, such as a <book-part>
Subtitle. In the article metadata, the article subtitle and title are identified with two different elements and tagged separately, using the <article-title> and <subtitle> elements. Within a bibliographic reference citation, the subtitle cannot be preserved separately as this Tag Set identifies no cited-subtitle elements.
For references using the <mixed-citation>, there are two choices:
Best Practice. Although this Tag Set cannot enforce either practice, retrieval performance will be enhanced if the subtitle is consistently placed within the <article-title> element (or the <source> element for book titles, proceedings titles, and other titles) for all cited material. Either with a <named-content> or as untagged text, the subtitle is easy to lose to searching. It is also not always obvious, particularly with historical or foreign material, which part of a multipart title is the main title and which the subtitle.
<!ELEMENT subtitle (#PCDATA %title-elements;)* >
(#PCDATA | email | ext-link | multi-link | uri | inline-supplementary-material | related-article | related-object | bold | italic | monospace | overline | overline-start | overline-end | roman | sans-serif | sc | strike | underline | underline-start | underline-end | alternatives | inline-graphic | private-char | chem-struct | inline-formula | tex-math | mml:math | abbrev | milestone-end | milestone-start | named-content | styled-content | fn | target | xref | sub | sup | break)*
Any combination of:
... <book-meta> <book-id>...</book-id> <book-title-group> <book-title>Sequence - Evolution - Function</book-title> <subtitle>Computational Approaches in Comparative Genomics</subtitle> </book-title-group> ... <publisher> <publisher-name>Kluwer Academic Publishers</publisher-name> <publisher-loc>Norwell, MA</publisher-loc></publisher> <permissions> <copyright-statement>© 2003 by Kluwer Academic Publishers.</copyright-statement> <copyright-year>2003</copyright-year> </permissions> <abstract>...</abstract> </book-meta> ...