APA استشهاد

Cunningham, W. P., & Cunningham, M. A. (2012). Environmental science: A global concern (12th ed.). McGraw Hill.

استشهاد بنمط شيكاغو

Cunningham, William P., و Marry Ann Cunningham. Environmental Science: A Global Concern. 12th ed. New York: McGraw Hill, 2012.

MLA استشهاد

Cunningham, William P., و Marry Ann Cunningham. Environmental Science: A Global Concern. 12th ed. McGraw Hill, 2012.