Armitage, K. B., & Schwartz, O. A. (2000). Social enhancement of fitness in yellow-bellied marmots. The National Academy of Sciences.
Chicago Style aipamenaArmitage, Kenneth B., and Orlando A. Schwartz. Social Enhancement of Fitness in Yellow-bellied Marmots. The National Academy of Sciences, 2000.
MLA aipamenaArmitage, Kenneth B., and Orlando A. Schwartz. Social Enhancement of Fitness in Yellow-bellied Marmots. The National Academy of Sciences, 2000.
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