APA (7th ed.) Citation

Cosman, M., Hamburger, P., & Keller, H. (1957). Musical sketchbook. Cassirer.

Chicago Style (17th ed.) Citation

Cosman, Milein, Paul Hamburger, and Hans Keller. Musical Sketchbook. Oxford: Cassirer, 1957.

MLA (9th ed.) Citation

Cosman, Milein, et al. Musical Sketchbook. Cassirer, 1957.