Deif, E.A., A. Galal, M.M. Fathi, and A. Zein El-Dein. 2007. “Immunocompetence of Two Broiler Strains Fed Marginal and High Protein Diets”. International Journal of Poultry Science 6 (12): 901–911. https://doi.org/10.3923/ijps.2007.901.911.