APA (7th ed.) Citation

Kafka, F., Milena, & Haas, W. (1952). Briefe an Milena. Schocken Books.

Chicago Style (17th ed.) Citation

Kafka, Franz, Milena, and Willy Haas. Briefe an Milena. New York: Schocken Books, 1952.

MLA (8th ed.) Citation

Kafka, Franz, et al. Briefe an Milena. Schocken Books, 1952.