“Efficacy of Intraoperative Subanaesthetic Dose of Ketamine on Post-Operative Analgesia for Patients Undergoing Single Level Lumbar Discectomy under General Anesthesia: A Placebo Control Randomized Clinical Study”. Asian Journal of Medical Sciences, vol. 14, no. 11, Nov. 2023, pp. 53-59, https://doi.org/10.3126/ajms.v14i11.56489.