Andika, Geri, and Bima Cahya Putra. 2019. “PENERAPAN ELECTRONIC CUSTOMER RELATIONSHIP MANAGEMENT (E-CRM) PADA SMA PGRI 117 KARANG TENGAH”. IDEALIS : InDonEsiA JournaL Information System 2 (3):173-78. https://jom.fti.budiluhur.ac.id/IDEALIS/article/view/573.