Chatha, Sohail Saqib, et al. “EVALUATION OF SINGLE PREOPERATIVE DOSE OF PREGABALIN IN TERMS OF POSTOPERATIVE PAIN AFTER LAPAROSCOPIC CHOLECYSTECTOMY: Single Preoperative Dose of Pregabalin”. Pakistan Armed Forces Medical Journal, vol. 68, no. 5, Oct. 2018, pp. 1358-61, https://www.pafmj.org/PAFMJ/article/view/2322.