Pasha, Muhammad Naeem, et al. “A Study to Compare 0.5% Hyperbaric Bupivacaine With 0.5% Isobaric Ropivacaine Intrathecally for Elective Lower Limb Surgery”. International Journal of Endorsing Health Science Research, vol. 10, no. 2, May 2022, pp. 172-8, doi:10.29052/IJEHSR.v10.i2.2022.172-178.