@INBOOK {IKEORGU:1989b,
title = {Effect of fertilizer and time of introduction of cassava or maize on productivity of yam and cassava-based intercrops in a humid ultisol},
author = {Ikeorgu, J. * and Unamma, R. P. A. and Ezumah, H. C. },
year = {1989},
type = {Cassava-based cropping systems research II},
pages = {36--41},
publisher = {International Institute of Tropical Agriculture (IITA)},
address = {Ibadan, Nigeria},
note = {RTB; Root and Tuber; Cassava},
}