APA
Kassam A., Fischer G W Et Al & Van Velthuizen H T. (1991). Agro-ecological land resources assessment for agricultural development planning: A case study of Kenya. Resources database and land productivity. Rome: FAO.
Chicago
Kassam A.H, Fischer G W Et Al and Van Velthuizen H T. 1991. Agro-ecological land resources assessment for agricultural development planning: A case study of Kenya. Resources database and land productivity. Rome: FAO.
Harvard
Kassam A., Fischer G W Et Al and Van Velthuizen H T. (1991). Agro-ecological land resources assessment for agricultural development planning: A case study of Kenya. Resources database and land productivity. Rome: FAO.
MLA
Kassam A.H, Fischer G W Et Al and Van Velthuizen H T. Agro-ecological land resources assessment for agricultural development planning: A case study of Kenya. Resources database and land productivity. Rome: FAO. 1991.