PENERAPAN MODEL WATEFALL PADA RANCANG BANGUN SISTEM INFORMASI PENJUALAN ONLINE HID BULLAES. jitk [Internet]. 2016 Aug. 15 [cited 2026 Mar. 26];2(1):1-4. Available from: https://ojs.nusamandiri.ac.id/index.php/jitk/article/view/226