The start-stop-single type is used for an attribute of musical elements that can be used for either multi-note or single-note musical elements, as for tremolos.
<xs:simpleType name="start-stop-single"><xs:annotation><xs:documentation>The start-stop-single type is used for an attribute of musical elements that can be used for either multi-note or single-note musical elements, as for tremolos.</xs:documentation></xs:annotation><xs:restriction base="xs:token"><xs:enumeration value="start"/><xs:enumeration value="stop"/><xs:enumeration value="single"/></xs:restriction></xs:simpleType>