Citazione Stile APA (7a Edizione)

Ehrlich, P. R., Ehrlich, A. H., & Holdren, J. P. (1977). Ecoscience: Population, resources, environment. W. H. Freeman.

Citazione stile Chigago Style (17a edizione)

Ehrlich, Paul R., Anne H. Ehrlich, e John P. Holdren. Ecoscience: Population, Resources, Environment. San Francisco: W. H. Freeman, 1977.

Citatione MLA (9a ed.)

Ehrlich, Paul R., et al. Ecoscience: Population, Resources, Environment. W. H. Freeman, 1977.