@ARTICLE {VANLAUWEa, title = {Utilization of rock phosphate by crops on a representative toposequence in the northern Guinea savanna zone of Nigeria: response by maize to previous herbaceous legume cropping and rock phospate treatments}, author = {Vanlauwe, B. and Diels, J. and Sanginga, P. and Carsky, R. and Deckers, J. and Merckx, R. }, journal = {Soil Biology and Biochemistry}, year = {2000}, volume = {32}, pages = {2079--2090}, }