Purves/Orians. (1987). The Science Of Biology. Sinauer Association Inc.
Čikaški stil citiranja (17. izdanje)Purves/Orians. The Science Of Biology. Sinauer Association Inc, 1987.
MLA način citiranja (8. izdanje)Purves/Orians. The Science Of Biology. Sinauer Association Inc, 1987.
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