APA (7th ed.) Citation

De Villiers, M., & Hirtle, S. (2002). Sahara: A natural history. Walker & Company.

Chicago Style (17th ed.) Citation

De Villiers, Marq, and Sheila Hirtle. Sahara: A Natural History. New York: Walker & Company, 2002.

MLA (9th ed.) Citation

De Villiers, Marq, and Sheila Hirtle. Sahara: A Natural History. Walker & Company, 2002.