Olson David M, Dinerstein Eric, Powell George V N, Wikramanayake Eric D
Conservation Science Program, World Wildlife Fund-US, 1250 24th Steet NW, Washington, D.C. 20037-1175, U.S.A., email
Conserv Biol. 2002 Feb;16(1):1-3. doi: 10.1046/j.1523-1739.2002.01612.x.