Patanavijit, Vorapoj. “Mathematical Tutorial of Discrete-Time Analysis of Sampling Rate Changing Concept for Digital Signal Processing and Digital Communication Prospective”. Progress in Applied Science and Technology 6, no. 2 (November 1, 2016): 58–72. accessed September 24, 2026. https://ph02.tci-thaijo.org/index.php/past/article/view/243141.