P. Parashar, A. Singh, M. K. Sharma, and D. L. Raval, “Comparison between isobaric levobupivacaine 0.5% and hyperbaric bupivacaine 0.5% in spinal anesthesia in lower limb surgeries and lower abdominal surgeries in adult patients”, Int J Res Med Sci, vol. 9, no. 2, pp. 418–422, Jan. 2021.