Used to mark text that should appear in an italic or slanted font for print or display
The intended meaning is that this element work as a toggle: if the formatting context already imposes italics (whether due to another <italic> element, a stylesheet, or some other means), then this element should turn italics off; another nested one would turn italics back on, and so on.
<!ELEMENT italic (#PCDATA %emphasized-text;)* >
(#PCDATA | hr | 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)*
Any combination of:
<addr-line>, <aff>, <alt-title>, <anonymous>, <article-title>, <attrib>, <award-id>, <bold>, <book-title>, <chapter-title>, <chem-struct>, <collab>, <collection-name>, <comment>, <compound-kwd-part>, <conf-loc>, <conf-name>, <conf-sponsor>, <copyright-statement>, <corresp>, <def-head>, <degrees>, <disp-formula>, <edition>, <element-citation>, <etal>, <ext-link>, <fax>, <funding-source>, <funding-statement>, <given-names>, <gov>, <inline-formula>, <inline-supplementary-material>, <institution>, <issue>, <issue-part>, <issue-title>, <italic>, <kwd>, <label>, <license-p>, <meta-value>, <mixed-citation>, <monospace>, <named-content>, <on-behalf-of>, <overline>, <p>, <part-title>, <patent>, <phone>, <prefix>, <preformat>, <price>, <product>, <publisher-loc>, <publisher-name>, <related-article>, <related-object>, <role>, <roman>, <sans-serif>, <sc>, <series>, <sig>, <sig-block>, <source>, <std>, <strike>, <styled-content>, <sub>, <subject>, <subtitle>, <suffix>, <sup>, <supplement>, <surname>, <target>, <td>, <term>, <term-head>, <textual-form>, <th>, <title>, <trans-source>, <trans-subtitle>, <trans-title>, <underline>, <uri>, <verse-line>, <volume>, <volume-id>, <volume-series>, <xref>
...
<sec id="bid.36">
<title>Microbial Genomes</title>
<p>... A CON entry, containing instructions on how to
put the pieces back together, is also made. The CON entry
contains descriptor information, such as source organism
and references, as well as a join statement providing
explicit instructions on how to generate the complete
genome from the pieces. The Accession number assigned to
the CON record is also added as a secondary Accession
number on each of the pieces that make up the complete
genome (see <xref ref-type="fig" rid="bid.37">Figure 2</xref>).
<fig id="bid.37">
<label>2</label>
<caption><title>A GenBank CON entry for a complete
bacterial genome.</title>
<p>The information toward the <italic>bottom</italic> of
the record describes how to generate the complete genome
from the pieces.</p>
</caption>
<graphic xmlns:xlink="http://www.w3.org/1999/xlink"
xlink:href="ch1f2" mime-subtype="gif"/>
</fig>
</p>
...
</sec>
...
format3.ent