@ARTICLE {MUTSAERS:1990,
title = {Farmers' maize yields in S.W. Nigeria and the effect of variety and fertilizer: An analysis of variability in on-farm trials},
author = {Mutsaers, H. J. W. and Walker, P. },
journal = {Field Crops Research},
year = {1990},
volume = {23},
pages = {265--278},
}