Coto, C.A., F. Yan, S. Cerrate, Z. Wang, P. Sacakli, and P.W. Waldroup. 2007. “Effects of Dietary Levels of Calcium and Nonphytate Phosphorus in Broiler Starter Diets on Total and Water-Soluble Phosphorus Excretion As Influenced by Phytase and Addition of 25-Hydroxycholecalciferol”. International Journal of Poultry Science 6 (12): 937–943. https://doi.org/10.3923/ijps.2007.937.943.