@INBOOK {KWARI:2011, title = {Soil fertility variability in relation to the yields of maize and soybean under intensifying cropping systems in the tropical savannas of northeastern Nigeria}, author = {Kwari, J. * and Kamara, A. and Ekeleme, F. * and Omoigui, L. *}, editor = {Bationo, A. * and Waswa, B. and Okeyo, J. M. and Maina, F. W. and Kihara, J. }, year = {2011}, month = {November}, volume = {1}, pages = {457--464}, chapter = {1 Part II}, publisher = {Springer}, address = {Netherlands}, isbn = {978-90-481-2541-8}, note = {In: Innovations as key to the green revolution in Africa: exploring the scientific facts}, doi = {10.1007/978-90-481-2543-2_47}, }