1. M. C. Paulk, B. Curtis, M. B. Chrissis and C. Weber, “Capability Maturity Model for Software.” https://resources.sei.cmu.edu/library/asset-view.cfm?assetid=11955.
2. “Organizational Project Management Maturity Model.” http://www.pmi.org/BusinessSolutions/Pages/OPM3.aspx.
3. “ISO 9004:2018 Quality management - Quality of an organization - Guidance to achieve sustained success”, 2018. https://www.iso.org/standard/70397.html.
4. “ISO/IEC 15504-1:2004 Information technology - Process assessment - Part 1: Concepts and vocabulary”, 2004. https://www.iso.org/standard/38932.html.
5. Methods and techniques for maturity assessment