de Souza Pinto, Jefferson, et al. “Proposal the Application of DMAIC Tools and Value Stream Mapping under the Perspective of the Lean Philosophy for Process Improvement: A Case Study”. Brazilian Journal of Operations & Production Management, vol. 14, no. 4, Dec. 2017, pp. 556-6, doi:10.14488/BJOPM.2017.v14.n4.a11.