A chemical expression, reaction, equation, etc. that is set apart within the text. This is an NLM not an APA element.
(#PCDATA | alt-text | long-desc | ext-link | break | bold | italic | monospace | overline | roman | sans-serif | sc | strike | underline | label | def-list | list | mml:math | named-content | styled-content | alternatives | array | graphic | preformat | fn | target | xref | sub | sup)*
Any combination of:
<chem-struct-wrap>, <inline-formula>, <label>, <named-content>, <styled-content>
display3.ent