APA (7th ed.) Zitazioa
West, G. C., & Butler, C. A. (2010). Do hummingbirds hum?: Fascinating answers to questions about hummingbirds. Rutgers University Press.
Chicago Style (17th ed.) Zitazioa
West, George C., eta Carol A. Butler. Do Hummingbirds Hum?: Fascinating Answers to Questions About Hummingbirds. New Brunswick, NJ: Rutgers University Press, 2010.
MLA (9th ed.) Zitazioa
West, George C., eta Carol A. Butler. Do Hummingbirds Hum?: Fascinating Answers to Questions About Hummingbirds. Rutgers University Press, 2010.
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