Megayanti, A., Roy Amrullah Ritonga, and Gustina. “UPGRADE SISTEM PENGAJUAN CUTI KARYAWAN BERBASIS PLATFORM PHP FRAMEWORK CODEIGNITER PADA KRAKATAU IT”. Jurnal Insan Unggul, vol. 14, no. 1, Apr. 2026, pp. 25-37, http://www.sttikom-iu.ac.id:8081/jurnaliu/index.php/01/article/view/191.