“Towards Integrating Six Sigma Approach: Service Level Agreement Measurement and Monitoring (A Malaysian It Outsourcing Case Study)”, TURCOMAT, vol. 12, no. 3, pp. 2191–2198, Apr. 2021, Accessed: Jun. 01, 2026. [Online]. Available: https://www.turcomat.org/index.php/turkbilmat/article/view/1166