Sharan, R., Singh, M., Pal Attri, J. and Dr Davinder Singh, D. 2016. Additive effect of butorphanol in supraclavicular brachial plexus block. International Journal of Medical Research and Review. 4, 6 (Jun. 2016), 910-917. DOI:https://doi.org/10.17511/ijmrr.2016.i06.08.