Varatorn, Rergchai. “Perioperative Transesophageal Echocardiography A Companion to Kaplan’s Cardiac Anaesthesi”. The Bangkok Medical Journal 7, no. 1 (February 20, 2014): 111. Accessed August 11, 2020. https://he02.tci-thaijo.org/index.php/bkkmedj/article/view/219641.