Sheldon, B., & Birkhead, T. (1994). REPRODUCTIVE ANATOMY OF THE CHAFFINCH IN RELATION TO SPERM COMPETITION.
Chicago-viite (17. p.)Sheldon, B., ja T. Birkhead. REPRODUCTIVE ANATOMY OF THE CHAFFINCH IN RELATION TO SPERM COMPETITION. 1994.
MLA-viite (9. p.)Sheldon, B., ja T. Birkhead. REPRODUCTIVE ANATOMY OF THE CHAFFINCH IN RELATION TO SPERM COMPETITION. 1994.
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