The effect of using six-sigma diffraction theory in improving productivity on the plastic containers production line at the  Al-Yaqout factory. The International Journal of Engineering & Information Technology (IJEIT), [S. l.], v. 14, n. 1, p. 95–101, 2025. DOI: 10.36602/ijeit.v14i1.592. Disponível em: https://ijeit.misuratau.edu.ly/index.php/ijeit/article/view/592. Acesso em: 21 dec. 2025.