Cunningham, W. P., & Saigo, B. W. (1999). Environmental Science: A Global Concern (5th ed.). McGraw Hill.
Cita Chicago (17th ed.)Cunningham, William P., i Barbara Woodworth Saigo. Environmental Science: A Global Concern. 5th ed. Boston: McGraw Hill, 1999.
Cita MLA (9th ed.)Cunningham, William P., i Barbara Woodworth Saigo. Environmental Science: A Global Concern. 5th ed. McGraw Hill, 1999.
Atenció: Aquestes cites poden no estar 100% correctes.