S. N. Khasanah, S. J. Kuryanti, H. Hermanto, and C. Adiwihardja, “IT-Helpdesk System Design With Waterfall Model (Case Study : Agung Podomoro Group): IT-Helpdesk System Design With Waterfall Model (Case Study : Agung Podomoro Group)”, Mantik, vol. 4, no. 1, pp. 56-60, May 2020.