@INBOOK {UNAMMA:1989, title = {Evaluation of the productivity of cassava-yam-maize intercrop in the rainforest zone of Nigeria}, author = {Unamma, R. P. A. and Udealor, A. and Ezulike, T. O. and Orkwor, G. C. and Ene, L. S. O. and Ikeorgu, J. * and Ezumah, H. C. }, year = {1989}, type = {Cassava-based cropping systems research II}, pages = {47--56}, publisher = {International Institute of Tropical Agriculture (IITA)}, address = {Ibadan, Nigeria}, note = {RTB; Root and Tuber}, }