Saifulloh, Benny. “PEMODELAN SISTEM INFORMASI PEMBELIAN BARANG DENGAN METODE BERBASIS OBYEK (OBJECT ORIENTED) STUDI KASUS: PT. AGS FOUR WINDS INDONESIA”. IDEALIS : InDonEsiA JournaL Information System, vol. 2, no. 1, Jan. 2019, pp. 36-41, https://jom.fti.budiluhur.ac.id/IDEALIS/article/view/1359.