APA-viite (7. p.)
Enger, E. D., & Smith, B. F. (2004). Environmental science: A study of interrelationships (9th ed.). McGraw-Hill Higher Education.
Chicago-viite (17. p.)
Enger, Eldon D., ja Bradley Fraser Smith. Environmental Science: A Study of Interrelationships. 9th ed. Boston: McGraw-Hill Higher Education, 2004.
MLA-viite (9. p.)
Enger, Eldon D., ja Bradley Fraser Smith. Environmental Science: A Study of Interrelationships. 9th ed. McGraw-Hill Higher Education, 2004.
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