3Jeffrey A. ,McNeely and Sara J. Scherr. Ecoagriculture:Strategies to Feed the World and Save Wild Biodiversity. Island press. 2003.
4Nelson M., R. Dudal, H.Gregersen, et al.1997. Report of the study on CGIAR Research, Washington,D.C.
5Mcclafferty, Bonnie. 2000. Summary of the state of global malnutrition. International food policy research institute, Washington, D.C.upublished, memo.
6World Resources Institute. 1998. World Resources Institute, Washington D.C.
7Gallup, J.L., J.D. Sachs and A.D. Mellinger. geopraphy and economic development [J] . International Regional Science Review,1999, 22 (2): 179-232
8Scheffer, Marten, S.Carpenter, et al. Catastrophic shifts in ecosystems [J] . Nature, 2001 (143): 591-596.
