Pereira, A. M., M. R. Silva, M. A. Domingues, and J. C. Sá. “Lean Six Sigma Approach to Improve the Production Process in the Mould Industry: A Case Study”. Quality Innovation Prosperity, vol. 23, no. 3, Nov. 2019, pp. 103-21, doi:10.12776/qip.v23i3.1334.