Tan, Zhan Feng, and Wan Nurshazwani Wan Zakaria. “COVID-19 Mandatory Self-Quarantine Monitoring System”. Evolution in Electrical and Electronic Engineering 2, no. 2 (November 15, 2021): 605–614. Accessed June 30, 2022. https://publisher.uthm.edu.my/periodicals/index.php/eeee/article/view/4156.