Mahmood, Amjad, et al. “TRANSCATHETER CLOSURE OF LARGE PERSISTENT DUCTUS ARTERIOSUS WITH THE MUSCULAR VENTRICULAR SEPTAL DEFECT DEVICE”. Pakistan Armed Forces Medical Journal, vol. 68, no. Suppl-1, Mar. 2018, pp. S14-17, https://pafmj.org/PAFMJ/article/view/3259.