@ARTICLE {EZUMAH:1992, title = {Importance and sustainability of root crops-based systems in sub-Saharan Africa}, author = {Ezumah, H. C. and Lawson, T. L. and Federer, W. T. and Awa, N. E. }, journal = {Journal of the West African Farming Systems Research Network}, year = {1992}, volume = {2}, number = {1}, pages = {15--30}, note = {RTB; Root and Tuber}, }