Ernes, Risa. “Application In Locker Security System With Double Bluetooth Media Using Microcontroller And Basic Programming Language”. Jurnal KomtekInfo 7, no. 1 (February 14, 2020): 58-66. Accessed April 2, 2020. http://lppm.upiyptk.ac.id/ojsupi/index.php/KOMTEKINFO/article/view/1221.