Ekmay, R.D., and C.N. Coon. “The Effect of Limestone Particle Size on the Performance of Three Broiler Breeder Purelines”. International Journal of Poultry Science, vol. 9, no. 11, Oct. 2010, pp. 1038–1042, https://doi.org/10.3923/ijps.2010.1038.1042.