Within bibliographic references (<element-citation> and <mixed-citation>), International Standard Book Number, the international code for identifying a particular version or printing of a book


ISBNs can be assigned to books, reports, standards documents, conference proceedings, and dissertations. The <isbn> element can be used to record all such numbers inside bibliographic citations (<element-citation> and <mixed-citation>). Within the ISBN, spacing, hyphens, and punctuation should be preserved. Within a mixed-style citation, the text “ISBN:”, if present, should be kept as text within the citation but not placed inside the <isbn> element. Within an element-style citation, the text “ISBN:”, if present, should be removed from the citation and also not placed inside the <isbn> element.

The @content-type attribute used to differentiate between ISBNs or explain the reason for a particular ISBN as needed.


content-type Type of Content

Content Model

<!ELEMENT  isbn         (#PCDATA %isbn-elements;)*                   >

Expanded Content Model



Text, numbers, or special characters, zero or more

This element may be contained in:

<element-citation>, <mixed-citation>, <product>, <related-article>, <related-object>


<given-names>Deborah A.</given-names>
<given-names>B. Tommie</given-names>
<source>Wildflowers of the Washington Area</source>
<publisher-name>Lippman, Ltd.</publisher-name>
<publisher-loc>Bethesda, MD</publisher-loc>
<isbn>0-23-8675-309</isbn>, includes a CD-ROM,
<price>$19.95</price> (Used 12.50 when available)