Gaya APA

BOTKIN, D, B., KELLER, E, A. (2000). Environmental Science: earth as a living planet (ed. 3). New York: John Wiley & Sons.

Gaya MLA

BOTKIN, Daniel, B.., KELLER, Edward, A.. "Environmental Science: earth as a living planet". ed. 3 New York: John Wiley & Sons, 2000. Text.