Phan Khánh Linh, Nguyễn Thị Anh Vân. Applying Six Sigma Method to Improve Product Quality of Automatic Water Valves: Online First: 30/06/2026. JTE [Internet]. 2026 Jun. 30 [cited 2026 Jul. 7];. Available from: https://www.jte.edu.vn/index.php/jte/article/view/2125