Udvardy, M. D. F. (1977). The Audubon Society field guide to North American birds--western region. Knopf : distributed by Random House.
Lua i Stíl Chicago (17ú heag.)Udvardy, Miklos D. F. The Audubon Society Field Guide to North American Birds--western Region. New York: Knopf : distributed by Random House, 1977.
Lua MLA (8ú heag.)Udvardy, Miklos D. F. The Audubon Society Field Guide to North American Birds--western Region. Knopf : distributed by Random House, 1977.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.