APA (7th ed.) Citation

Osborn, C. S., & Osborn, S. B. (1939). The conquest of a continent. [The Science Press Printing Company].

Chicago Style (17th ed.) Citation

Osborn, Chase Salmon, and Stella Brunt Osborn. The Conquest of a Continent. Michigan: [The Science Press Printing Company], 1939.

MLA (9th ed.) Citation

Osborn, Chase Salmon, and Stella Brunt Osborn. The Conquest of a Continent. [The Science Press Printing Company], 1939.