Enger, E. D. (2000). Environmental Science: A Study of Interrelationships. MC Graw Hill.
Chicago-viite (17. p.)Enger, Eldon D. Environmental Science: A Study of Interrelationships. New York: MC Graw Hill, 2000.
MLA-viite (9. p.)Enger, Eldon D. Environmental Science: A Study of Interrelationships. MC Graw Hill, 2000.
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