APA (7th ed.) Zitazioa
Cotter, D. J. (1993). Learning biology today. Mosby.
Chicago Style (17th ed.) Zitazioa
Cotter, David J. Learning Biology Today. St. Louis: Mosby, 1993.
MLA (9th ed.) Zitazioa
Cotter, David J. Learning Biology Today. Mosby, 1993.
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