1. Soils of Tabora Region, Tanzania, Tabora Rural Integrated Development Project, Land Use Component;Acres,1983
2. Methodology of integrated surveys;Christian,1964
3. Soil Survey and Land Evaluation;Dent,1981
4. The agricultural development of the Gambia: an agricultural, environmental and socio-economic analysis;Dunsmore,1975
5. Assessment of potential land resources through random sample surveys;Guinard;World Crops,1974