APA Style

EHRLICH, P, R., Ehrlich, A, H. (1970). Population resources environment: issues in human ecology (1). San Francisco: W. H. Freeman and Company.

MLA Style

EHRLICH, PAUL, R.., Ehrlich, Anne, H.. "Population resources environment: issues in human ecology". 1 San Francisco: W. H. Freeman and Company, 1970. Text.