kholifah, safitri, Farida Djumiati Sitania, and Yudi Sukmono. “Design Air Conditioner Maintenance SOP Based on ISO 9001:2015”. Journal of Industrial Engineering and Education 2, no. 1 (April 28, 2024): 108–125. Accessed September 30, 2025. https://jiee.bksti.org/index.php/iee/article/view/27.