QUALITY CONTROL OF SANDWICH PANEL PRODUCTS USING SEVEN TOOLS AND SIX SIGMA METHODS. International Journal of Economic Integration and Regional Competitiveness, [S. l.], v. 2, n. 8, p. 21–39, 2025. DOI: 10.61796/ijeirc.v2i8.390. Disponível em: https://e-journal.antispublisher.id/index.php/IJEIRC/article/view/390. Acesso em: 26 nov. 2025.