Zhang, B.; Caldas, J. V.; Coon , C. N. Effect of Dietary Calcium Intake and Limestone Solubility on Egg Shell Quality and Bone Parameters for Aged Laying Hens. Int. J. Poult. Sci. 2017, 16 (4), 132–138. https://doi.org/10.3923/ijps.2017.132.138.