Ehrlich, P. . R., & Ehrlich, A. H. (1970). Population resources environment. W.H. Freeman.
Chicago Style aipamenaEhrlich, Paul R., and Anne H. Ehrlich. Population Resources Environment. Sanfrancisco: W.H. Freeman, 1970.
MLA aipamenaEhrlich, Paul R., and Anne H. Ehrlich. Population Resources Environment. W.H. Freeman, 1970.
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