M. S., Ameen Abdulla; E. G., Kavilal. Analytical Investigation of Higher Education Quality Improvement by Using Six Sigma Approach. HighTech and Innovation Journal, [S. l.], v. 3, n. 2, p. 196–206, 2022. DOI: 10.28991/HIJ-2022-03-02-07. Disponível em: https://hightechjournal.org/index.php/HIJ/article/view/207. Acesso em: 10 oct. 2025.