Maulida, Hilda, Ihsan Riga Valendi, Olland Nugraha, and Fadhli Ranuharja. “Prototyping a Secure Key Management System: Integrating RFID and Keypad Technologies for Enhanced Safe Protection”. Journal of Hypermedia & Technology-Enhanced Learning 1, no. 2 (June 30, 2023): 91–99. Accessed September 21, 2025. https://edutech-journals.org/index.php/j-hytel/article/view/73.