@INBOOK {JEFWA:2014, title = {Do commercial biological and chemical products increase crop yields and economic returns under smallholder farmer conditions?}, author = {Jefwa, J. * and Pypers, P. and Jemo, M. and Thuita, M. and Mutegi, E. and Laditi, M. A and Faye, A. * and Kavoo, A. M. * and Munyahali, W. and Herrmann, L. and Atieno, M. and Okalebo, J. R. and Yusuf, A. A. * and Ibrahim, A. * and Ndung'u-Magiroi, K. W. * and Asrat, A. * and Muletta, D. * and Ncho, C. * and Kamaa, M. and Lesueur, D. }, year = {2014}, pages = {81--96}, chapter = {7}, publisher = {Springer}, address = {Switzerland}, isbn = {978-3-319-07662-1}, note = {In: B. Vanlauwe et al. (eds.), Challenges and Opportunities for Agricultural Intensification of the Humid Highland Systems of Sub-Saharan Africa; WAHub; CAHub}, doi = {10.1007/978-3-319-07662-1_7}, }