Friedman, F. (2003). Practical guide to environmental management (9th ed.). Washington, D.C.: Environmental Law Institute.
Παραπομπή Chicago StyleFriedman, Frank. Practical Guide to Environmental Management. 9th ed. Washington, D.C.: Environmental Law Institute, 2003.
Παραπομπή MLAFriedman, Frank. Practical Guide to Environmental Management. 9th ed. Washington, D.C.: Environmental Law Institute, 2003.
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