@ARTICLE {HULUGALLE:1991, title = {Effect of cassava-based cropping systems on physicochemical properties of soil and earthworm casts in a tropical Alfisol}, author = {Hulugalle, N. and Ezumah, H. C. }, journal = {Agriculture, Ecosystems and Environment}, year = {1991}, volume = {35}, number = {1}, pages = {55--63}, issn = {0167-8809}, note = {RTB; Root and Tuber; Cassava}, }