Patel, Hemangini M, and Bansari N Kantharia. “A STUDY ON COMPARISON OF INTRAVENOUS BUTORPHANOL WITH INTRAVENOUS FENTANYL FOR PREMEDICATION IN GENERAL ANESTHESIA”. National Journal of Medical Research, vol. 6, no. 01, Mar. 2016, pp. 89-91, https://njmr.in/index.php/file/article/view/324.