@INBOOK {OLANIYAN:2001, title = {The dynamics of the root and tuber cropping systems in the middle belt of Nigeria}, author = {Olaniyan, G. and Manyong, V. and Oyewole, B. }, year = {2001}, type = {Root crops in the 21st century: proceedings of the 7th Triennial Symposiu,m of the International Soceity for Tropical Root Crops (ISTRC) - Africa Branch, Oct 1998}, pages = {75--82}, publisher = {International Soceity for Tropical Root Crops (ISTRC) - Africa Branch; Government of Benin}, }