Hussain, I., Z. U. Zahid, M. S. Jibran, and S. Shawana. “CORRELATION OF AGE AND DEFECT SIZE OF ISOLATED SECUNDUM ATRIAL SEPTAL DEFECT WITH PULMONARY ARTERY PRESSURE”. Pakistan Heart Journal, vol. 50, no. 3, Dec. 2017, doi:10.47144/phj.v50i3.1310.