Madiyono, Bambang, Hanafi Trisnohadi, and Maemunah Affandi. 1981. “HIS Bundle Electrocardiogram in Children With Secundum Atrial Defects and Patent Ductus Arteriosus”. Paediatrica Indonesiana 21 (1-2), 1-10. https://doi.org/10.14238/pi21.1-2.1981.1-10.