1. V. R. Young, ‘Mammalian Protein Metabolism,’ Vol. 4, ed. by H. N. Munro, Academic Press inc., New York, N. Y., 1970, p. 585.
2. National Academy of Sciences, ‘Nutrient Requirements of Domestic Animals No. 10: Nutrient Requirements of Laboratory Animals,’ 2nd ed., National Academy of Sciences, Washington, D.C., 1972, p. 64.
3. G. W. Snedecor and W. G. Cochran, ‘Statistical Methods, 6th ed.’ The Iowa State University Press, Ames, Iowa, 1967, Chapter 4.