M. Q. Islam, H. Begum, A. Akhtaruzzaman, and U. S. Khatun, “Study on Efficacy of Nalbuphine Hydrochloride as Pre-Emptive Analgesic – Comparison With Diclofenac Sodium after Open Cholecystectomy”, j Bangladesh Soc Anaesthesiologists, vol. 20, no. 2, pp. 39–44, Dec. 2009.