Fauziyah, Begum, Muslimatul Khoiriyah, Abdul Hakim, and Abdul Wafi. “Development of Urea Sensor Based on Colorimetric Method and Digital RGB Analysis”. International Journal of Engineering & Technology 8, no. 1.9 (January 26, 2019): 332–334. Accessed May 1, 2024. https://sciencepubco.com/index.php/ijet/article/view/26680.