1. ISO (International Organization for Standardization) (1998) Information technology: Quality of Service—Framework. ISO/IEC 13236:1998
2. ITU-T Rec. E.800 (1994) Terms and definitions related to quality of service and network performance including dependability
3. ITU-T Rec. G.100/P.10 (2008) Vocabulary for performance and quality of service, amendment 2: new definitions for inclusion in Recommendation P.10/G.100
4. ITU-T Rec. G.107 (2005) The E-model, a computational model for use in transmission planning
5. ITU-T Rec. P.563 (2004) Single-ended method for objective speech quality assessment in narrow-band telephony applications