Sangkatip, Rittichai, Manus Sriswat, Kosuchon Satayotin, and Wattanachai Prasong. 2023. “Improvement of Electric Fan Manufacturing Process by Lean Six Sigma Technique”. Journal of Advanced Development in Engineering and Science 9 (26). Babgkok, Thailand:14-24. https://ph03.tci-thaijo.org/index.php/pitjournal/article/view/921.