Παραπομπή APA

Eckholm, E. P. (1982). Down to earth: Environment and human needs. Affiliated East-West Press.

Παραπομπή Chicago Style

Eckholm, Erik P. Down to Earth: Environment and Human Needs. New Delhi: Affiliated East-West Press, 1982.

Παραπομπή MLA

Eckholm, Erik P. Down to Earth: Environment and Human Needs. Affiliated East-West Press, 1982.