Cita APA (7th ed.)

Keller, E. A. (1992). Environmental Geology (6th ed.). Macmillan.

Cita Chicago (17th ed.)

Keller, Edward A. Environmental Geology. 6th ed. New York: Macmillan, 1992.

Cita MLA (9th ed.)

Keller, Edward A. Environmental Geology. 6th ed. Macmillan, 1992.