Syakur, Yasir Abdan, Elohansen Padang, and Baina Afkril. 2023. “DESIGN OF A RIVER WATER LEVEL MEASURING INSTRUMENT USING AJ-SR04M ULTRASONIC SENSOR”. Jurnal Natural 19 (1), 60 -67. https://doi.org/10.30862/jn.v19i1.231.