Number, name, or other identifier of a sub-part of a journal issue.
This is not the machine-readable internal identifier such as a DOI or SICI; that is tagged with the related element <issue-id>. Nor is it the name or number of an entire issue; that is tagged with <issue>.
Some journals seldom or never use sub-issues, and therefore seldom or never use this element. Journals might, however, use it for a large journal issue whose print edition is bound in more than one separate part; those parts might well be numbered or named distinctly despite being parts of the same issue. Distinct numbers or names for each bound portion would then be tagged with this element, while the common identifier of the entire issue would be tagged with <issue>.
<!ELEMENT issue-part (#PCDATA %issue-part-elements;)* >
(#PCDATA)*
Text, numbers, or special characters, zero or more
<article-meta>, <element-citation>, <front-stub>, <mixed-citation>, <product>, <related-article>, <related-object>
In article metadata
...
<article-meta>
<title-group>
<article-title>Chron’s Disease: Treatment Strategies</article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name><surname>Layman</surname>
<given-names>Steven</given-names></name>
</contrib>
<contrib contrib-type="author">
<name><surname>Aug</surname>
<given-names>Lisa</given-names></name>
</contrib>
</contrib-group>
<aff>Gastrointestinal Department, St
Mark’s Hospital, Lexington, KY</aff>
<author-notes><fn><p>Correspondence to: S. Layman <email>slay@stmark.org</email></p></fn></author-notes>
<pub-date pub-type="pub"><day>27</day><month>03</month><year>1994</year></pub-date>
<volume>12</volume>
<issue>3</issue>
<issue-sponsor>Pharmaceutical Research Association</issue-sponsor>
<issue-part>2</issue-part>
<fpage>522</fpage>
<lpage>528</lpage>
...
</article-meta>
...
In a mixed-style bibliographic references (punctuation and spacing preserved):
...
<ref>
<mixed-citation publication-type="journal" publication-format="print">
<string-name><surname>Gosse</surname>,
<given-names>P</given-names></string-name>,
...
<string-name><surname>Clementy</surname>,
<given-names>J</given-names></string-name>.
<article-title>Reduction in arterial distensibility
in hypertensive patients as evaluated by ambulatory
measurement of the QKD interval is correlated with
concentric remodeling of the left ventricle</article-title>.
<source>Am J Hypertens</source>. <year>1999</year>
<month>Dec</month>;<volume>12</volume>
(<issue>12</issue> <issue-part>Pt 1-2</issue-part>):
<fpage>1252</fpage>-<lpage>1255</lpage>.</mixed-citation>
</ref>
...
JATS-common0.ent