Beer, M. de, and C.N. Coon. 2009. “The Effect of Different Feed Restriction Programs and Dietary L-Carnitine Supplementation on Hepatic Lipogenesis, Plasma Heterophil to Lymphocyte Ratio and Yolk IgY Content of Broiler Breeder Hens”. International Journal of Poultry Science 8 (4): 328–341. https://doi.org/10.3923/ijps.2009.328.341.