1. DeLong B. Estimating world GDP, one million B.C.—present, 1998 (Brad DeLong’s homepage, www.j-bradford-delong.net/TCEH/1998 Draft/World GDP/Estimating World GDP.html).
2. Monitoring the world economy 1820–1992;Madisson,1995
3. Energy and ecology;Gates,1995
4. Factor Four. Doubling wealth—halving resource use;Von Weizäcker,1997
5. The skeptical environmentalist;Lomborg,1998