APA (7th ed.) Citation

Ditmars, R. L. (1939). A field book of North American snakes. Doubleday, Doran & company, inc..

Chicago Style (17th ed.) Citation

Ditmars, Raymond Lee. A Field Book of North American Snakes. New York: Doubleday, Doran & company, inc., 1939.

MLA (9th ed.) Citation

Ditmars, Raymond Lee. A Field Book of North American Snakes. Doubleday, Doran & company, inc., 1939.