Othman, O., S. El-Fiky, N. Hassan, E. Mahfouz, and E. Balabel. “Genetic Variations of &#946- and K-Casein Genes in Egyptian Sheep Breeds”. Journal of Applied Biosciences, vol. 64, no. 1, May 2013, pp. 4858–4866, doi:10.4314/jab.v64i1.88475.