Columbia subject headings:
D'Annunzio, Gabriele, 1863-1938. Fedra.
Pizzetti, Ildebrando, 1880-1968. Fedra.
Harvard subject headings:
D'Annunzio, Gabriele, 1863-1938--Musical settings.
D'Annunzio, Gabriele, 1863-1938. Fedra
Opera--Italy--20th century
Opera--Italy--20th century--Librettos.
Pizzetti, Ildebrando, 1880-1968--Criticism and interpretation.
Pizzetti, Ildebrando, 1880-1968. Fedra.
Princeton subject headings:
D'Annunzio, Gabriele, 1863-1938. Fedra.
Pizzetti, Ildebrando, 1880-1968. Fedra.