Koirala, Siddhartha, et al. “Efficacy of Oral Carvedilol Premedication in Attenuating the Hemodynamic Response to Direct Laryngoscopy and Endotracheal Intubation”. Birat Journal of Health Sciences, vol. 5, no. 2, Oct. 2020, pp. 1071-5, doi:10.3126/bjhs.v5i2.31408.