TAO, C.-J.; CHEN, S.-C.; HSIEH, C.-T. Assessing Product Satisfaction Performance using 6-Sigma Methodology and S/N Ratio Approach - the case of PDA. International Journal of Industrial Engineering: Theory, Applications and Practice, [S. l.], v. 16, n. 1, p. 51–60, 2009. DOI: 10.23055/ijietap.2009.16.1.204. Disponível em: https://journals.sfu.ca/ijietap/index.php/ijie/article/view/204. Acesso em: 18 may. 2024.