1. Abdul-Rahman, A.A. and Habib, S.A. (1989). Allelopathic effects of alfalfa (Medicago sativa) on bladygrass (Imperata cylindrica). Journal of Chemical Ecology 15: 2289–2301.
2. Aggarwal, P.K. and Garrity (1987). Intercropping of legumes to contribute nitrogen in low-input upland rice-based cropping systems. Proceedings International Symposium Nutrient Management for Crop Production in Tropical Farming Systems. Makang, Indonesia.
3. Al-Sayed, A.A. and Montasser, S.A. (1986). The role of ascorbic and glutamic acids in controlling the root-knot nematode, Meloidogyne javanica. Egyptian Journal of Phytopathology 18: 143–138.
4. Al-Sayed, A.A. and Thomson, I.J. (1988). Meloidogyne incognita and tomato response to thiamine, ascorbic acid, L-arginine and L-glutamic acid. Journal of Nematology. 20: 451–456.
5. Altieri, M.A. (1987). Agroecology: The Scientific Basis of Alternative Agriculture. London: Intermediate Technology, pp.227.