APA (7th ed.) Citation

Degerbl, M., & Freuchen, P. (1935). Mammals. Gyldendal.

Chicago Style (17th ed.) Citation

Degerbl, Magnus, and Peter Freuchen. Mammals. Copenhagen: Gyldendal, 1935.

MLA (9th ed.) Citation

Degerbl, Magnus, and Peter Freuchen. Mammals. Gyldendal, 1935.