APA (7th ed.) Citation

Gurnell, J. (1987). The natural history of squirrels. Facts on File.

Chicago Style (17th ed.) Citation

Gurnell, J. The Natural History of Squirrels. New York, N.Y.: Facts on File, 1987.

MLA (9th ed.) Citation

Gurnell, J. The Natural History of Squirrels. Facts on File, 1987.