Santoso, Andy, and Holong Marisi Simalango. “Model Analisis Sistem Purchase Order Pada UD. Budi Indo Perkasa”. Media Informatika 20, no. 1 (March 31, 2021): 19–30. Accessed April 20, 2024. https://journal.likmi.ac.id/index.php/media-informatika/article/view/45.