S. A. Mohamed, A. M. Hussam, S. A. Abdallah, K. A. Sarhan, and A. M. Shaban, “Ondansetron Is an Effective Alternative to Decrease the Incidence of Postspinal Hypotension in Healthy Subjects Undergoing Infra-Umbilical Surgeries Compared To Combined Volume Loading and Vasoconstrictors: Randomized Controlled Trial”, Open Access Maced J Med Sci, vol. 6, no. 12, pp. 2363–2368, Dec. 2018.