@ARTICLE {EHUI:1990a, title = {Economic analysis of soil erosion effects in alley cropping, no-till and bush fallow systems in southwestern Nigeria}, author = {Ehui, S. K. and Kang, B. and Spencer, D. }, journal = {Agricultural Systems}, year = {1990}, volume = {34}, number = {4}, pages = {349--368}, issn = {0308-521X}, }