Y. Martínez-Aguilar, R. Rodríguez-Bertot, C. Betancur-Hurtado, D. Más-Toro, C. Olmo-González, and M. Valdivié-Navarro, “Dietary Supplementation of Increasing Levels of DLMethionine and L-Lysine in Hypoproteic Diets for Laying Hens Improves Productivity and Egg Quality”, Cien. Agri., vol. 12, no. 1, pp. 7–14, Jan. 2015.