Yogesh Tilkar, Shailendra Dawer, Rahul Meda, and Ranjita Aske Dawer, “Comparison of Bupivacaine 0.5% + Normal Saline , Bupivacaine 0.5%+ Fentanyl (50 μG) & Bupivacaine 0.5%+ Clonidine (150 μG) Intrathecally for Postoperative Analgesia in lower limb Orthopedic Surgeries”, Int. J. Heal. Clin. Res., vol. 4, no. 13, pp. 255–260, Jul. 2021.