Farming systems and poverty : improving farmers' livelihoods in a changing world / Dixon, John Gibbon, David P. Gulliver, Aidan. Hall, Malcolm. Agriculture Farmers Rural development Food supply Rural poor Sustainable agriculture 338 FAO 2001 A068 Co. Rome : FAO ; Washington, D.C. : World Bank, 2001. 2001. Text viii, 412 p. :