Παραπομπή APA

Conkin, P. K. A. (2007). The state of the earth: Environmental challenges on the road to 2100.

Παραπομπή Chicago Style

Conkin, Paul K; Author. The State of the Earth: Environmental Challenges on the Road to 2100. Hyderabad, Universities Press (India) Ltd, 2007.

Παραπομπή MLA

Conkin, Paul K; Author. The State of the Earth: Environmental Challenges on the Road to 2100. 2007.