1. ISO. ISO/IEC TR 15504-1:1998 Information technology – Software process assessment – Part 1: Concepts and introductory guide
2. ISO. ISO/IEC TR 15504-2:1998 Information technology – Software process assessment – Part 2: A reference model for processes and process capability
3. ISO. ISO/IEC TR 15504-3:1998 Information technology – Software process assessment – Part 3: Performing an assessment
4. ISO. ISO/IEC TR 15504-4:1998 Information technology – Software process assessment – Part 4: Guide to performing assessments
5. ISO. ISO/IEC TR 15504-5:1998 Information technology – Software process assessment – Part 5: An assessment model and indicator guidance