APA引文

Verdi, G. Rigoletto: An opera in four acts. F. Rullman.

芝加哥风格引文

Verdi, Guiseppe. Rigoletto: An Opera in Four Acts. New York: F. Rullman.

MLA引文

Verdi, Guiseppe. Rigoletto: An Opera in Four Acts. F. Rullman.