Tao, Chia-Jen, Shui-Chuan Chen, and Chin-Tsung Hsieh. “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 16, no. 1 (March 31, 2009): 51–60. Accessed May 18, 2024. https://journals.sfu.ca/ijietap/index.php/ijie/article/view/204.