<elementSpec rend="add" ident="music" module="MEI.shared"><desc rend="replace">Contains a single musical text of any kind, whether unitary or composite, for example,
an etude, opera, song cycle, symphony, or anthology of piano solos.</desc>
<constraintSpec ident="check_controlEventLinking" scheme="schematron">
<constraint>
<sch:rule context="mei:*[@tstamp]">
<sch:assert test="not(@startid)">An element with @tstamp may not have @startid as well (and vice versa).</sch:assert>
</sch:rule>
<sch:rule context="mei:*[@tstamp2]">
<sch:assert test="not(@endid)">An element with @tstamp2 may not have @endid as well (and vice versa).</sch:assert>
</sch:rule>
</constraint>
</constraintSpec></elementSpec>