APA (7th ed.) Citation

Simmel, G., Wolff, K. H., & Bendix, R. (1955). Conflict. Free Press.

Chicago Style (17th ed.) Citation

Simmel, Georg, Kurt H. Wolff, and Reinhard Bendix. Conflict. Glencoe, Illinois: Free Press, 1955.

MLA (9th ed.) Citation

Simmel, Georg, et al. Conflict. Free Press, 1955.