Boonchuduang, Somrutai, Wipharat Juthasantikul, Amphan Chantarokorn, and Wirat Wasinwong. 2013. “Effects of Using Video Guided about Deep-Breathing Exercise for Patient Preparation before Receiving General Anesthesia”. Srinagarind Medical Journal 27 (2):139-46. https://li01.tci-thaijo.org/index.php/SRIMEDJ/article/view/11102.