ONWUCHEKWA, PH.D, D. SIX-SIGMA ANALYTICAL TOOL AND THE EFFECTIVENESS OF PAINT MANUFACTURING FIRMS IN PORT HARCOURT, RIVERS STATE. BW Academic Journal, [S. l.], 2025. Disponível em: https://www.bwjournal.org/index.php/bsjournal/article/view/2646. Acesso em: 27 jul. 2026.