Novia, Rekha, and Wella . “ITIL 2011: Maturity Level of Service Operation”. IJNMT (International Journal of New Media Technology) 6, no. 1 (August 30, 2019): 50-54. Accessed November 21, 2024. https://ejournals.umn.ac.id/index.php/IJNMT/article/view/1058.