1. Altieri MA, Francais CA, Schoonhaven A van and Doll JD (1978) A review of insect prevalence in maize (Zea mays L.) and bean (Phaseolus vulgaris L.) polycultural systems. Field Crops Research 1: 33?49
2. Anderson GW and Batini FE (1979) Clover and crop production under 13 to 15 year old Pinus radiata. Aust J Exp Agric Anim Husb 19: 363?368
3. Bogdan AV (1977) Tropical pasture and fodder plants. London, Longmans
4. Burt RL, Rotar PP, Walker JL and Silvey MW (1983) The role of Centrosema, Desmodium and Stylosanthes in improving tropical pastures. Boulder, Colorado, Westview Press
5. Cannell MGR (1983) Plant population and yield of tree and herbaceous crops. In: Huxley PA, ed, Plant research and agroforestry, pp 489?502. Nairobi, International Council for Research in Agroforestry (ICRAF)