Ehrlich, P. R., & Ehrlich, A. H. (1972). Population, resources, environment : issues in human ecology / (by) Paul R. Ehrlich (and) Anne H. Ehrlich: Issues in human ecology (2nd ed.). Freeman.
Chicago Style (17th ed.) CitationEhrlich, Paul R., and Anne H. Ehrlich. Population, Resources, Environment : Issues in Human Ecology / (by) Paul R. Ehrlich (and) Anne H. Ehrlich: Issues in Human Ecology. 2nd ed. San Francisco: Freeman, 1972.
MLA (9th ed.) CitationEhrlich, Paul R., and Anne H. Ehrlich. Population, Resources, Environment : Issues in Human Ecology / (by) Paul R. Ehrlich (and) Anne H. Ehrlich: Issues in Human Ecology. 2nd ed. Freeman, 1972.
Warning: These citations may not always be 100% accurate.