Cita APA (7th ed.)

Boyd, R., & Silk, J. B. (1997). How humans evolved. W.W. Norton & Company.

Cita Chicago (17th ed.)

Boyd, Robert, i Joan B. Silk. How Humans Evolved. New York: W.W. Norton & Company, 1997.

Cita MLA (9th ed.)

Boyd, Robert, i Joan B. Silk. How Humans Evolved. W.W. Norton & Company, 1997.