Conkin, P. (2007). The state of the earth: Environmental challenges on the road to 2100. Universities Press.
Lua i Stíl Chicago (17ú heag.)Conkin, Paul. The State of the Earth: Environmental Challenges on the Road to 2100. Hyderabad: Universities Press, 2007.
Lua MLA (9ú heag.)Conkin, Paul. The State of the Earth: Environmental Challenges on the Road to 2100. Universities Press, 2007.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.