1. Carter , M. R. , and B. A. Steward . 1996 . Structure and organic matter storage in agricultural soils . Lewis Publishers , Boca Raton , FL .
2. Casenave , A., andC. Valentin.1989.Soil surface status in the sahelian zone. Influence on infiltration. Office de Recherche Scientifique des Territoires d'Outre Mer, Paris.
3. Soil management for Alfisols in the semiarid tropics: erosion, enrichment ratios and runoff