APA (7th ed.) Citation

Ehrlich, P. R., & Ehrlich, A. H. (1970). Population resources environment: Issues in human ecology. W. H. Freeman.

Chicago Style (17th ed.) Citation

Ehrlich, Paul R., and Anne H. Ehrlich. Population Resources Environment: Issues in Human Ecology. San Francisco: W. H. Freeman, 1970.

MLA (9th ed.) Citation

Ehrlich, Paul R., and Anne H. Ehrlich. Population Resources Environment: Issues in Human Ecology. W. H. Freeman, 1970.