Long-term Effects of Crops Residues Management on Soil Chemical Properties and Yields in Cotton - Maize - Sorghum Rotation System in Burkina Faso

(1) Inz. Krzysztof Skowron, Department of Microbiology, Nicolaus Copernicus University in Torun, Collegium Medicum of L. Rydygier in Bydgoszcz, Poland.