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2. Yamamoto, L., & Beerends, J. G. (1997). Impact of network performance parameters on the end-to-end perceived speech quality. In Proceedings of Expert ATM Traffic Symposium. Mykonos, Greece, Sep. 1997.
3. International Telecommunication Union. (1996). Methods for subjective determination of transmission quality. ITU Recommendation P.800, August 1996.
4. International Telecommunication Union. (2001). Perceptual evaluation of speech quality (PESQ), an objective method for end-to-end speech quality assessment of narrowband telephone networks and speech codecs. ITU-T Recommendation P.862, Feb. 2001.
5. International Telecommunication Union. (2003). Mapping function for transforming P.862 raw result scores to MOS-LQO. ITU-T Recommendation P.862.1, Nov. 2003