Perrin,William F, & Wursig,Bernd Thewissen, J. (2009). Encyclopedia of marine mammals (2nd ed.). Elsevier.
Chicago Style aipamenaPerrin,William F, and J.G.M Wursig,Bernd Thewissen. Encyclopedia of Marine Mammals. 2nd ed. Amsterdam: Elsevier, 2009.
MLA aipamenaPerrin,William F, and J.G.M Wursig,Bernd Thewissen. Encyclopedia of Marine Mammals. 2nd ed. Elsevier, 2009.
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