R. A. Sanmiguel-Plazas, G. R. Mejía-Rojas, L. M. Lozano-Covaleda, and R. D. Castañeda-Serrano, “Evaluation of different calcium grain sizes in laying hens diet”, Cien. Agri., vol. 13, no. 2, pp. 67–72, Nov. 2016.