Columbia subject headings:
Librettists.
Libretto.
Mozart, Wolfgang Amadeus, 1756-1791. Operas.
Harvard subject headings:
Librettists.
Libretto.
Mozart, Wolfgang Amadeus, 1756-1791. Operas.
Princeton subject headings:
Librettists--18th century.
Mozart, Wolfgang Amadeus, 1756-1791--Criticism and interpretation.
Mozart, Wolfgang Amadeus, 1756-1791. Operas.