Silitonga, R., L. Emysah, and C. Lubis. “Seven Diseases As Main Causes of Death In Department of Child Health Dr. Pirngadi General Hospital”. Paediatrica Indonesiana, Vol. 28, no. 11-12, Aug. 2019, pp. 250-4, doi:10.14238/pi28.11-12.1988.250-4.