APA (7th ed.) Citation

Howell, S. N. G., & Webb, S. (1995). A guide to the birds of Mexico and northern Central America. Oxford University Press.

Chicago Style (17th ed.) Citation

Howell, Steve N. G., and Sophie Webb. A Guide to the Birds of Mexico and Northern Central America. Oxford: Oxford University Press, 1995.

MLA (9th ed.) Citation

Howell, Steve N. G., and Sophie Webb. A Guide to the Birds of Mexico and Northern Central America. Oxford University Press, 1995.