1. Brewbaker JL (1987)Leucaena: a multipurpose tree genus for tropical agroforestry. In: Steppler HA and Nair PKR (eds) Agroforestry: A Decade of Development, pp 289?323. ICRAF, Nairobi, Kenya
2. World Soil Resources Report;FAO/UNESCO,1988
3. Kwapata MB, Chiyenda SS and Kanyama-Phiri GY (1990) Maize yield response under alley cropping. In: Saka AR, Bunderson WT and Maghembe JA (eds) Agroforestry Research and Development in Malawi, pp 186?196. Proceedings of Symposium, 4?10 November, 1990, Bvumbwe, Malawi
4. Lundgren B and Nair PKR (1986) Agroforestry for soil conservation In: EI-Swaify SS, Moldenhauer WC and Andrew LO (eds) Soil Erosion and Conservation, pp 703?717. Soil Conservation Society of America
5. Nair PKR (1987) The role of trees in soil productivity and protection. In: Nair PKR (ed) Agroforestry System in the Tropics, pp 567?589. Kluwer Academic Publishers, Dordrecht, The Netherlands