Assertion: libretto | /r/CreatedBy | the composer
Facets:
value: himself
type: OTHER
value: more often
type: DEGREE
value: sometimes
type: TEMPORAL
Source sentences:
text: Sometimes it's written by the composer her/himself, more often by someone else.
text: The libretto was written by the composer, with assistance from Vladimir Belsky [ru], Vladimir Stasov, and others.