APA (7th ed.) Citation

Ridgely, R. S., & Tudor, G. (1989). The birds of South America. Oxford Univ. Pr.

Chicago Style (17th ed.) Citation

Ridgely, Robert S., and Guy Tudor. The Birds of South America. Oxford u.a: Oxford Univ. Pr, 1989.

MLA (9th ed.) Citation

Ridgely, Robert S., and Guy Tudor. The Birds of South America. Oxford Univ. Pr, 1989.