@INBOOK {DUMSDAY:1975, title = {Evaluating systems of soil conservation: results from a bio-economic model}, author = {Dumsday, R. G. and Flinn, J. C. }, year = {1975}, month = {October}, type = {IITA Papers of Staff in the Agricultural Economics Sub-Program 1973 - October1975}, pages = {267--286}, publisher = {IITA}, }