Hasibuan, Doli, dan Alfonsus Situmorang. “Implentasi Customer Relationship Management Berbasis Web Pada Toko Sablon Medan”. Jurnal TIMES 9, no. 2 (Desember 20, 2020): 13–24. Diakses Mei 12, 2024. http://ejournal.stmik-time.ac.id/index.php/jurnalTIMES/article/view/631.