Hutagalung, Samuel. “Water Flow & Temperature Control to Increase Extraction Yield of Light-Roasted Coffee Beans”. Ultima Computing : Jurnal Sistem Komputer 14, no. 2 (December 28, 2022): 54–59. Accessed September 18, 2025. https://ejournals.umn.ac.id/index.php/SK/article/view/2810.