Citazione Stile APA (7a Edizione)

Ehrlich, P., & Ehrlich, A. H. (1972). Population, resources, environment: Issues in human ecology. W. H. Freeman.

Citazione stile Chigago Style (17a edizione)

Ehrlich, Paul, e Anne H. Ehrlich. Population, Resources, Environment: Issues in Human Ecology. San Francisco: W. H. Freeman, 1972.

Citatione MLA (9a ed.)

Ehrlich, Paul, e Anne H. Ehrlich. Population, Resources, Environment: Issues in Human Ecology. W. H. Freeman, 1972.