Sancheti Vikram Nirmal, Chordiya Mayur Ashok, and K. Senthilkumaran. “Development of Monolayer Elementary Osmotic Tablet of Verapamil Hydrochoride”. World Journal of Pharmaceutical Sciences, vol. 2, no. 12, Dec. 2014, pp. 1934-40, https://wjpsonline.com/index.php/wjps/article/view/monolayer-elementary-osmotic-tablet-verapamil.