@INPROCEEDINGS {IWUAFOR:1991, title = {Effects of different tillage and crop residue management systems on chemical properties of an Alfisol}, author = {Iwuafor, E. * and Kang, B. and Ike, I. F. }, booktitle = {Soil tillage and agricultural sustainability: proceedings of the 12th International Conference of the International Soil Tillage Research Organization, 8-12 Jul 1991, Ibadan Nigeria}, year = {1991}, pages = {53--63}, publisher = {International Soil Tillage Research Organization}, address = {Columbus, Ohio}, }