Patel, S. A., P. U. Patel, and S. M. Patel. “Simultaneous Spectrophotometric Determination of Diazepam and Propranolol Hydrochloride in Tablets”. Current Research in Pharmaceutical Sciences, Vol. 1, no. 1, Dec. 2011, pp. 25-30, https://www.crpsonline.com/index.php/crps/article/view/30.