1. Bring, S.V., C.A. Richard, and M.V. Zaehringer, J. Nutr. 85:400 (1965).
2. Erdman, J.W., Jr., and P.A. Lachance, Nutr. Repts. Int. 10:227 (1974).
3. Erdman, J.W., Jr., J.G. Elliott, and P.A. Lachance, Nutr. Repts. Int. 16:37 (1977).
4. Erdman, J.W., Jr., J.G. Elliot, and P.A. Lachance, Nutr. Repts. Int. 16:47 (1977).
5. National Research Council, Nutrient Requirements of Domestic Animals: Nutrient Requirements of Laboratory Animals, 3rd Ed., NAS Washington, DC (1978), p. 20.