Environmental Careers Organization & ebrary, Inc. (2004). The ECO guide to careers that make a difference. Island Press.
Chicago-viite (17. p.)Environmental Careers Organization ja Inc ebrary. The ECO Guide to Careers That Make a Difference. Washington: Island Press, 2004.
MLA-viite (9. p.)Environmental Careers Organization ja Inc ebrary. The ECO Guide to Careers That Make a Difference. Island Press, 2004.
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