S. M. Shareef, I. Sridhar, K. M. Dakshayani, Y. V. Rao, and B. Santhamma, “Evaluation of the effects of tramadol and diclofenac alone and in combination on post-cesarean pain”, Int J Basic Clin Pharmacol, vol. 3, no. 3, pp. 470–473, Jan. 2017.