R. K. Chhetri, M. Shrestha, and R. P. Shrestha, “Factors affecting conversion of laparoscopic to open cholecystectomy”, J. Soc. Surg. Nepal, vol. 20, no. 1, pp. 13–16, Jun. 2017, doi: 10.3126/jssn.v20i1.24385.