Faizon, Wan Muhammad Ezzadam, and Nor'aisah Sudin. “Autonomous Self Check-In KeyBox and Reservation for Homestay Operation”. Evolution in Electrical and Electronic Engineering, vol. 4, no. 2, Oct. 2023, pp. 369-78, https://penerbit.uthm.edu.my/periodicals/index.php/eeee/article/view/10933.