Records the total number of either a) the references (<ref>) or (more properly) b) the number of citations (<citation>) that appear in the bibliographic reference list (<ref-list>) for a book. This count is (roughly) the number of sources cited in the book.
Many elements in this DTD Suite were created explicitly for import conversion, that is, so that the intellectual work of tagging done by publishers would not be discarded when they converted material from another DTD to the NCBI Book DTD and NCBI Collection DTDs. The count elements are a perfect example of this rationale; they are conversion elements and should only be tagged if present in the original source.
The count elements are modeled as EMPTY elements (that is, elements that have no content and store their real values in one or more attributes) because the majority of DTDs that were examined in the course of preparing this DTD Suite used this mechanism, an inheritance of the older MAJOUR-header DTD.
<!ELEMENT ref-count EMPTY >
This is an EMPTY element
<book> <book-meta> <book-id pub-id-type="other">handbook</book-id> <book-title-group> <book-title>The NCBI Handbook</book-title> </book-title-group>... <counts> <fig-count count="98"/> <table-count count="40"/> <equation-count count="0"/> <ref-count count="115"/> <page-count count="532"/> <word-count count="149852"/> </counts> </book-meta> <book-front>...</book-front> <body>...</body> <back>...</back> </book>
articlemeta.ent