Dyfyniad APA

Botkin, D. B., & Keller, E. A. (2000). Environmental science: Earth as a living planet (3rd ed.). New York: J. Wiley.

Dyfyniad Arddull Chicago

Botkin, Daniel B., và Edward A. Keller. Environmental Science: Earth As a Living Planet. 3rd ed. New York: J. Wiley, 2000.

Dyfyniad MLA

Botkin, Daniel B., và Edward A. Keller. Environmental Science: Earth As a Living Planet. 3rd ed. New York: J. Wiley, 2000.

Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.