APA (7th ed.) Citation

Verdi, G., Cammarano, S., Macfarren, N., & Stevenson, E. I. (1926). Il trovatore = The troubadour: An opera in four acts. G. Schirmer.

Chicago Style (17th ed.) Citation

Verdi, Giuseppe, Salvatore Cammarano, Natalia Macfarren, and E. Irenaeus Stevenson. Il Trovatore = The Troubadour: An Opera in Four Acts. New York: G. Schirmer, 1926.

MLA (9th ed.) Citation

Verdi, Giuseppe, et al. Il Trovatore = The Troubadour: An Opera in Four Acts. G. Schirmer, 1926.