Cita APA (7th ed.)

Cunningham, W. P. (1994). Understanding our environment: An introduction. Wm. C. Brown.

Cita Chicago (17th ed.)

Cunningham, William P. Understanding Our Environment: An Introduction. Dubuque, IA: Wm. C. Brown, 1994.

Cita MLA (9th ed.)

Cunningham, William P. Understanding Our Environment: An Introduction. Wm. C. Brown, 1994.