Nguyen , Le Hoang Minh, et al. “ENDOCARDIAL 2D SPECKLE-TRACKING ECHOCARDIOGRAPHY IN PATIENTS WITH CORONARY ARTERY DISEASE”. Vietnamese Journal of Radiology and Nuclear Medicine, no. 01, Dec. 2021, pp. 46-51, https://vjrnm.edu.vn/index.php/vjrnm/article/view/1146.