Used to mark text in which the case of the content should not be changed, even if the content around it is styled to all upper case or all lower.
As an example, the word “PhD” should not be changed during display to either “phd” or “PHD”. An another example, the lower case unit of measure the micro would change magnitude if translated to upper case.
<!ELEMENT fixed-case (#PCDATA %emphasized-text;)* >
(#PCDATA | email | ext-link | uri | inline-supplementary-material | related-article | related-object | hr | bold | fixed-case | italic | monospace | overline | overline-start | overline-end | roman | sans-serif | sc | strike | underline | underline-start | underline-end | ruby | alternatives | inline-graphic | private-char | chem-struct | inline-formula | tex-math | mml:math | abbrev | index-term | index-term-range-end | milestone-end | milestone-start | named-content | styled-content | fn | target | xref | sub | sup | x | break)*
Any combination of:
<abbrev>, <addr-line>, <aff>, <alt-title>, <anonymous>, <article-title>, <attrib>, <award-id>, <bold>, <book-title>, <book-volume-id>, <book-volume-number>, <chapter-title>, <chem-struct>, <code>, <collab>, <comment>, <compound-kwd-part>, <compound-subject-part>, <conf-acronym>, <conf-loc>, <conf-name>, <conf-num>, <conf-sponsor>, <conf-theme>, <copyright-statement>, <corresp>, <date-in-citation>, <def-head>, <degrees>, <disp-formula>, <edition>, <element-citation>, <email>, <etal>, <ext-link>, <fax>, <fixed-case>, <funding-source>, <funding-statement>, <given-names>, <gov>, <inline-formula>, <inline-supplementary-material>, <institution>, <issue>, <issue-part>, <issue-title>, <italic>, <kwd>, <label>, <license-p>, <meta-name>, <meta-value>, <mixed-citation>, <monospace>, <named-content>, <nav-pointer>, <on-behalf-of>, <overline>, <p>, <part-title>, <patent>, <phone>, <prefix>, <preformat>, <price>, <product>, <publisher-loc>, <publisher-name>, <rb>, <related-article>, <related-object>, <role>, <roman>, <sans-serif>, <sc>, <see>, <see-also>, <see-also-entry>, <see-entry>, <self-uri>, <series>, <sig>, <sig-block>, <source>, <speaker>, <std>, <std-organization>, <strike>, <string-conf>, <string-date>, <string-name>, <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>, <unstructured-kwd-group>, <uri>, <verse-line>, <volume>, <volume-id>, <volume-series>, <volume-title>, <x>, <xref>
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<p>In <fixed-case>eBook</fixed-case> publishing, it is
important ...</p>
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