1. Bech-Andersen S (1984) Tryptophan determination in feedstuffs (Personal Communication)
2. Difco (1968) Difco Supplementary Literature. Detroit: Difco Laboratories
3. Frigg M (1976) Bio-availability of biotin in cereals. Poultry Sci 55:2310?2318
4. Juliano BO (1972) The rice caryopsis and its composition. In: Houston DF (ed) Rice, Chemistry and Technology. Minnesota: AACC, pp 16?74
5. Latham MC (1969) Human Nutrition in Tropical Africa. Rome: FAO