1. Total carbon and nitrogen in the soils of the world
2. 1999. Management options for reducing CO2 concentrations in the atmosphere by increasing carbon sequestration in the soil. Dutch National Research Programme on Global Air Pollution and Climate Change, Bilthoven.
3. The economic linkages between rural poverty and land degradation: some evidence from Africa
4. 1998. L' Intensification Agricole au Sahel. Editions Karthala: Paris.
5. 1980. Charactères hydro-morphologiques et possibilités rizicoles des sols de la vallée de Kamobeul-Bolon. BCEOM-IRAT, Direction de l' Equipement: Dakar (Senegal).