Roshid, Mohammad Harun Or, et al. “A Comparative Study Between Intravenous Tramadol Versus Lidocaine Pretreatment in Reducing Pain on Propofol Injection”. Journal of Chittagong Medical College Teachers’ Association, vol. 32, no. 2, Dec. 2021, pp. 90-94, doi:10.3329/jcmcta.v32i2.66501.