T. N. Wulandari Siagian, H. H. Nuha, and R. Yasirandi, “Footstep Recognition Using Mel Frequency Cepstral Coefficients and Artificial Neural Network”, J. RESTI (Rekayasa Sist. Teknol. Inf.) , vol. 4, no. 3, pp. 497 - 503, Jun. 2020.