Patmasari, Raditiana, et al. “DESIGN AND IMPLEMENTATION OF LEARNING TOOLS TO READ THE BRAILLE LETTERS BASED ON VOICE PROCESSING AND ARDUINO USING MEL FREQUENCY CEPSTRAL COEFFICIENT AND K-NEAREST NEIGHBOR METHOD”. JMECS (Journal of Measurements, Electronics, Communications, and Systems), vol. 6, no. 1, June 2020, pp. 28-33, doi:10.25124/jmecs.v6i1.2019.