APA (7th ed.) Citation

Rorem, N., & Koch, K. (1973). Bertha: One act opera. Boosey & Hawkes.

Chicago Style (17th ed.) Citation

Rorem, Ned, and Kenneth Koch. Bertha: One Act Opera. New York: Boosey & Hawkes, 1973.

MLA (9th ed.) Citation

Rorem, Ned, and Kenneth Koch. Bertha: One Act Opera. Boosey & Hawkes, 1973.

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