M. Z. Dini, A. Rakhmatsyah, and A. A. Wardana, “Detection of Oxygen Levels (SpO2) and Heart Rate Using a Pulse Oximeter for Classification of Hypoxemia Based on Fuzzy Logic”, J. Ilm. Tek. Elektro Komput. Dan Inform, vol. 8, no. 1, pp. 17–26, Apr. 2022.