Gaya APA

Cunningham, M, A., Cunningham, W, P. (2006). Principles of Environmental Science : Inquiry & Applications (3th ed.) . New York: McGraw-Hill.

Gaya MLA

Cunningham, Mary, Ann., Cunningham, William, P.. "Principles of Environmental Science : Inquiry & Applications (3th ed.)". New York: McGraw-Hill, 2006. Text.