Columbia subject headings:
Boito, Arrigo, 1842-1918--Congresses.
Boito, Arrigo, 1842-1918. Mefistofele--Congresses.
Libretto--Congresses.
Opera--Italy--Congresses.
Harvard subject headings:
Boito, Arrigo, 1842-1918--Congresses.
Boito, Arrigo, 1842-1918. Mefistofele--Congresses.
Libretto--Congresses.
Opera--Italy--Congresses.
Princeton subject headings:
Boito, Arrigo, 1842-1918--Congresses.
Boito, Arrigo, 1842-1918. Mefistofele--Congresses.
Libretto--Congresses.
Opera--Italy--Congresses.