Cita APA (7th ed.)

Capell, R. (1948). Opera (2a. ed.). Ernest Benn Limited.

Cita Chicago (17th ed.)

Capell, Richard. Opera. 2a. ed. Londres: Ernest Benn Limited, 1948.

Cita MLA (9th ed.)

Capell, Richard. Opera. 2a. ed. Ernest Benn Limited, 1948.