PASARIBU, B. T.; MUJANAH, S.; FIANTO, A. Y. A. Analysis of Lean Six Sigma Modeling in Efforts to Improve Operational Performance at Royal Surabaya Hospital. International Journal of Economics (IJEC), [S. l.], v. 4, n. 1, p. 682–693, 2025. DOI: 10.55299/ijec.v4i1.1376. Disponível em: https://ejournal.ipinternasional.com/index.php/ijec/article/view/1376. Acesso em: 5 dec. 2025.