Conkin, P. K. A. (2007). The state of the earth: Environmental challenges on the road to 2100.
Chicago Style aipamenaConkin, Paul K; Author. The State of the Earth: Environmental Challenges on the Road to 2100. Hyderabad, Universities Press (India) Ltd, 2007.
MLA aipamenaConkin, Paul K; Author. The State of the Earth: Environmental Challenges on the Road to 2100. 2007.
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