APA (7th ed.) Citation

Sonntag, C. F. (1924). On the anatomy, physiology, and pathology of the orang-outan. [publisher not identified].

Chicago Style (17th ed.) Citation

Sonntag, Charles F. On the Anatomy, Physiology, and Pathology of the Orang-outan. [Place of publication not identified]: [publisher not identified], 1924.

MLA (9th ed.) Citation

Sonntag, Charles F. On the Anatomy, Physiology, and Pathology of the Orang-outan. [publisher not identified], 1924.