Kurnia, Hibarkah, Krisna Budi Juliantoro, Suhendra Suhendra, Ahmad Turmudi Zy, and Apriyani Apriyani. 2023. “Combination of Lean Thinking and A3 Problem-Solving Methods to Reduce the Cost of Purchasing Cleaning Agents in a Paint Manufacturer in Indonesia”. SINERGI 28 (1). Jakarta, Indonesia:103-14. https://doi.org/10.22441/sinergi.2024.1.011.