Cintya, Cindy, and R.Fanry Siahaan. 2020. “Implementation of the Client-Server System for Ordering Food and Beverages With the Android Platform Using the Waterfall Method (Case Study: Maxx Coffee Prima Ap Kualanamu Store)”. Journal of Intelligent Decision Support System (IDSS) 3 (3):31-39. https://www.idss.iocspublisher.org/index.php/jidss/article/view/13.