Columbia subject headings:
Harvard subject headings:
Alcestis, Queen, consort of Admetus, King of Pherae--Drama.
Calzabigi, Ranieri de, 1714-1795.
Eurydice (Greek mythological character)--Drama.
Gluck, Christoph Willibald, Ritter von, 1714-1787
Opera--18th century--History and criticism.
Operas--Librettos
Orpheus (Greek mythological character)--Drama.
Princeton subject headings:
Drama.