APA (7th ed.) Citation

Verdi, G., & Duprez, E. (1890). Rigoletto: Opéra en 4 actes. Grus.

Chicago Style (17th ed.) Citation

Verdi, Giuseppe, and Edouard Duprez. Rigoletto: Opéra En 4 Actes. Paris: Grus, 1890.

MLA (9th ed.) Citation

Verdi, Giuseppe, and Edouard Duprez. Rigoletto: Opéra En 4 Actes. Grus, 1890.

Warning: These citations may not always be 100% accurate.