Bahri, Saeful, and Taufik Hidayatulloh. “Penerapan Coloring Graph Pada Sistem Pengingat Dan Penjadwalan Imunisasi Dasar Lengkap”. CESS (Journal of Computer Engineering, System and Science), vol. 3, no. 2, Aug. 2018, pp. 128-33, https://jurnal.unimed.ac.id/2012/index.php/cess/article/view/9895.