1. Andreasen, B. and Larsen, B., 1976, Ceruloplasmin polymorphism and parentage test in Hereford cattle, Acta vet. scand., 17: 264.
2. Flagstad, T., 1976, Lethal trait A 46 in cattle. Intestinal zinc absorption. Nord. Vet.-Med., 28: 160.
3. Reetz, I. and Feder, H., 1974, Ceruloplasmin, Kupfer-und Eisengehalt im Blutplasma beim Schwein und ihre Beziehungen zu Leistungseigenschaften, Proc. 1st World Congr. Genetics appl. Livestock Prod., Madrid, 3: 1159.
4. Wegger, I., 1985, Variations in trace element status of calves and their relation to trace element dependent enzymes and ascorbic acid, Ann. Rep. Sterility Res. Inst., 28: 125.
5. Wiener, G., Suttle, N.F., Field, A.C., Herbert, J.G. and Woolliams, J.A., 1978, Breed differences in copper metabolism in sheep, J. Agric. Sci., 91: 433.