Yavari, Hamid Reza, et al. “Microleakage Comparison of Four Dental Materials As Intra-Orifice Barriers in Endodontically Treated Teeth”. Iranian Endodontic Journal, vol. 7, no. 1, Dec. 2011, pp. 25-30, doi:10.22037/iej.v7i1.2727.