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2. C. Vaishnav, Voice over Internet Protocol (VoIP): The Dynamics of Technology and Regulation, M.S. Thesis, Massachusetts Institute of Technology (2006)
3. International Telecommunication Union (ITU), The Status of Voice over Internet Protocol (VOIP) Worldwide, 2006, New Initiatives Programme, Document: FoV/04, 12 Jan 2007
4. H. Schulzrinne, S. Casner, R. Frederick, V. Jacobson, RTP: A Transport Protocol for Real-Time Applications, RFC-1889, Jan 1996
5. T. Smura, H. Hämmäinen, The role of VoIP: future evolution paths of voice communication, in Proceedings of 1st International CICT Conference, Denmark, 2004