Hikmaturokhman, Alfin, Lintang Setyo Palupi, Norma Amalia, Achmad Rizal Danisya, and Toha Ardi Nugraha. “4G LTE Evolved Packet Core Planning With Call Switch Fallback Technology”. Journal of Telecommunication, Electronic and Computer Engineering (JTEC) 10, no. 1-6 (February 5, 2018): 133–136. Accessed June 23, 2024. https://jtec.utem.edu.my/jtec/article/view/3680.