Gray, O. S. (1970). Cases and materials on environmental law. Washington, D.C: The Bureau of National Affairs.
Παραπομπή Chicago StyleGray, Oscar S. Cases and Materials On Environmental Law. Washington, D.C: The Bureau of National Affairs, 1970.
Παραπομπή MLAGray, Oscar S. Cases and Materials On Environmental Law. Washington, D.C: The Bureau of National Affairs, 1970.
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