Misran, Muhamad Affiq Bin, Bilgaiyan, Anubha, AND Hattori, Reiji. " Optical Ray Tracing Simulation by Using Monte Carlo Method for Reflectance-based Photoplethysmography Sensor in Human Skin and Fingertip Model" Computational And Experimental Research In Materials And Renewable Energy [Online], Volume 5 Number 2 (11 November 2022)