Hasibuan, D., dan A. Situmorang. “Implentasi Customer Relationship Management Berbasis Web Pada Toko Sablon Medan”. Jurnal TIMES, vol. 9, no. 2, Desember 2020, hlm. 13-24, https://ejournal.stmik-time.ac.id/index.php/jurnalTIMES/article/view/631.