Esmaeili, Behnaz, et al. “Coronal Discoloration Induced by Calcium-Enriched Mixture, Mineral Trioxide Aggregate and Calcium Hydroxide: A Spectrophotometric Analysis”. Iranian Endodontic Journal, vol. 11, no. 1, Jan. 2016, pp. 23-28, doi:10.22037/iej.v11i1.8864.