Cita APA (7a ed.)

Pullman, P., Pullman, P., & Long, G. (1981). Ancient civilizations. Wheaton.

Cita Chicago Style (17a ed.)

Pullman, P., Philip Pullman, y Gary Long. Ancient Civilizations. Exeter: Wheaton, 1981.

Cita MLA (9a ed.)

Pullman, P., et al. Ancient Civilizations. Wheaton, 1981.