Shrestha, B., S. P. Acharya, and A. Roshana. “Comparison of Intrathecal Bupivacaine With or Without Fentanyl for Urosurgeries”. Journal of Society of Anesthesiologists of Nepal, vol. 1, no. 1, Oct. 2015, pp. 18-21, doi:10.3126/jsan.v1i1.13584.