<catchwords> (catchwords) describes the system used to ensure correct ordering of the quires or
similar making up a codex, incunable, or other object typically by means of annotations
at the foot of the page. [11.3.7 Catchwords, Signatures, Secundo Folio]
<sch:rule context="tei:catchwords"> <sch:assert test="ancestor::tei:msDesc or ancestor::tei:egXML">The <sch:name/> element should not be used outside of msDesc.</sch:assert> </sch:rule>