APA (7th ed.) Citation

Breysig, K., George, S., & Valeton, M. (1960). Castrum Peregrini. Castrum Peregrini Press.

Chicago Style (17th ed.) Citation

Breysig, Kurt, Stefan George, and Michiel Valeton. Castrum Peregrini. Amsterdam: Castrum Peregrini Press, 1960.

MLA (8th ed.) Citation

Breysig, Kurt, et al. Castrum Peregrini. Castrum Peregrini Press, 1960.