Muhadi, Muhadi, Sally A Nasution, Rudi Putranto, and Kuntjoro Harimurti. “The Ability of Detecting Heart Rate Variability With the Photoplethysmography to Predict Major Adverse Cardiac Event in Acute Coronary Syndrome”. Acta Medica Indonesiana 48, no. 1 (September 19, 2016): 48. Accessed May 1, 2026. https://www.actamedindones.org/index.php/ijim/article/view/137.