Ribeiro, Marlos Barbosa, et al. “Canal Transportation and Centering Ability of Curved Root Canals Prepared Using Rotary and Reciprocating Systems”. Brazilian Journal of Oral Sciences, vol. 14, no. 3, Sept. 2015, pp. 214-8, https://periodicos.sbu.unicamp.br/ojs/index.php/bjos/article/view/8641312.