Liu, Z. et al. 2004. Influence of Added Synthetic Lysine for First Phase Second Cycle Commercial Leghorns with the Methionine+Cysteine/Lysine Ratio Maintained at 0.75. International Journal of Poultry Science. 3, 3 (Feb. 2004), 220–227. DOI:https://doi.org/10.3923/ijps.2004.220.227.