Botkin, D. B., & Keller, E. A. (2003). Environmental science: Earth as a living planet (4th ed.). New York: Wiley.
Chicago Style aipamenaBotkin, Daniel B., và Edward A. Keller. Environmental Science: Earth As a Living Planet. 4th ed. New York: Wiley, 2003.
MLA aipamenaBotkin, Daniel B., và Edward A. Keller. Environmental Science: Earth As a Living Planet. 4th ed. New York: Wiley, 2003.
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