Cita APA (7th ed.)

Pipkin, B. W., & Trent, D. D. (1997). Geology and the environment (2nd ed.). Wadsworth Publishing Co.

Cita Chicago (17th ed.)

Pipkin, Bernard W., i D. D. Trent. Geology and the Environment. 2nd ed. Belmont, California: Wadsworth Publishing Co, 1997.

Cita MLA (9th ed.)

Pipkin, Bernard W., i D. D. Trent. Geology and the Environment. 2nd ed. Wadsworth Publishing Co, 1997.