Dyfyniad APA

Wright, R. T., & Nebel, B. J. (2002). Environmental science: Toward a sustainable future (Eighth edition.). Pearson Education.

Dyfyniad Arddull Chicago

Wright, Richard T., and Bernard J. Nebel. Environmental Science: Toward a Sustainable Future. Eighth edition. Upper Saddle River, New Jersey: Pearson Education, 2002.

Dyfyniad MLA

Wright, Richard T., and Bernard J. Nebel. Environmental Science: Toward a Sustainable Future. Eighth edition. Pearson Education, 2002.

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