1. The optimum length of planned fallows;Ahn,1979
2. Decline of soil fertility due to intensification of land use by shifting agriculturalists in Belize, Central America;Arnason;Agroecosystems,1982
3. Land tenure issues in the forestry and agroforestry project contexts;Bruce,1987
4. Resource Book on Sustainable Agriculture in the Uplands,1990
5. Soil conservation strategies for upland areas of Indonesia;Carson,1989