“Akuisisi Data Sinyal Photoplethysmograph (PPG) Menggunakan Photodioda”. Jurnal ELEMENTER (Elektro dan Mesin Terapan) 2, no. 2 (November 30, 2016): 32–41. Diakses September 19, 2026. http://slashroot.id/index.php/elementer/article/view/187.