APA (7th ed.) Citation

Beethoven, L. v. (1907). Fidelio: An opera in two acts. G. Schirmer.

Chicago Style (17th ed.) Citation

Beethoven, Ludwig van. Fidelio: An Opera in Two Acts. New York: G. Schirmer, 1907.

MLA (9th ed.) Citation

Beethoven, Ludwig van. Fidelio: An Opera in Two Acts. G. Schirmer, 1907.