Rifki, Muhamad Sazeli, Fiky Farma, Anton Komaini, Endang Sepdanius, Alimuddin, and Novadri Ayubi. “Development of Sit Up Measuring Tools Based on Arduino and Ultrasonic Sensors With Android Applications”. International Journal of Interactive Mobile Technologies (iJIM) 16, no. 08 (April 26, 2022): 182–189. Accessed August 17, 2024. https://online-journals.org/index.php/i-jim/article/view/30673.