Cita APA (7th ed.)

Ehrlich, P. R., & Ehrlich, A. H. (1970). Population Resources Environment: Issues in Human Ecology. W. H. Freeman and Company.

Cita Chicago (17th ed.)

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

Cita MLA (9th ed.)

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