Citazione Stile APA (7a Edizione)

Darwin, C., Barrett, P. H., & Freeman, R. B. (1988). Variation of animals and plants under domestication, 1. Pickering.

Citazione stile Chigago Style (17a edizione)

Darwin, Charles, Paul H. Barrett, e R. B. Freeman. Variation of Animals and Plants Under Domestication, 1. London: Pickering, 1988.

Citatione MLA (8a ed.)

Darwin, Charles, et al. Variation of Animals and Plants Under Domestication, 1. Pickering, 1988.