R. Bhattarai, B. Paudel, S. Subba, and C. R. Das, “Caudal Epidural Block for Ureteroscopic Lithotripsy (Ursl): A Prospective Study”, Birat J. Health Sci., vol. 5, no. 1, pp. 942–945, Jun. 2020, doi: 10.3126/bjhs.v5i1.29630.