E. Deif, A. Galal, M. Fathi, and A. Z. El-Dein, “Immunocompetence of Two Broiler Strains Fed Marginal and High Protein Diets”, Int. J. Poult. Sci., vol. 6, no. 12, pp. 901–911, Nov. 2007, doi: 10.3923/ijps.2007.901.911.