1. ARC, 1981. The Nutrient Requirements of Pigs. Commonwealth Agricultural Bureaux, Slough, London.
2. The metabolic requirement for amino acids in ruminants;Asplund,1994
3. Effect of ration on the nutritive quality of rumen microbial protein;Bergen;J. Anim. Sci.,1968
4. New strategy for optimizing amino acid supply to growing pigs;Boisen,1993
5. Ideal protein – and its suitability to characterize protein quality in pig feeds. A review;Boisen;Acta Agric. Scand. Sect. A, Anim. Sci.,1997