Achmad Deddy Kurniawan, Bambang Kurniawan, Rika Melyani, and Yuda Irawan. 2023. “Automatic Dispenser Prevents Covid Transmission Using Ultrasonic Sensor and Arduino Uno”. Journal of Applied Social and Informatics Science 5 (1):1-12. https://e-journal.ptti.info/index.php/jasis/article/view/107.