@BOOK {MANYONG:1996b, title = {Macrocharacterization of agricultural systems in Central Africa; an overview: RCMP Research monograph, No. 22}, author = {Manyong, V. and Smith, J. and Weber, S. S. and Jagtap, S. and Oyewole, B. }, series = {RCMP Research monograph, No. 22}, year = {1996}, publisher = {International Institute of Tropical Agriculture (IITA)}, address = {Ibadan, Nigeria}, note = {56p.}, }