Names elements that may be used inside elements that are really expected to be data characters (#PCDATA) and not to contain any of these things
This Parameter Entity is even simpler than the %simple-phrase; Parameter Entity. Note that there is only inline math, and there are no links. This Parameter Entity is for modeling elements that an authoring DTD could restrict to merely data characters (#PCDATA), but that a repository DTD dare not, since it needs to be able to handle the less mainstream cases.
<!ENTITY % simple-text "| %emphasis.class; | %inline-display.class; | %inline-math.class; | %phrase.class; | %subsup.class; " >