Manangi, M.K., and C.N. Coon. “The Effect of Calcium Carbonate Particle Size and Solubility on the Utilization of Phosphorus from Phytase for Broilers”. International Journal of Poultry Science, vol. 6, no. 2, Jan. 2007, pp. 85–90, https://doi.org/10.3923/ijps.2007.85.90.