Vroomen, J., Collier, R. and Mozziconacci, S. (1993) Duration and Intonation in Emotional Speech. Proceedings of the Third European Conference on Speech Communication and Technology, Berlin, 22-25 September 1993, 577-580.
 Campbell, W.N., Isard, S., Monaghan, A.L.C. and Verhoeven, J. (1990) Duration, Pitch and Diphones in the CSTR TTS System. Proceedings of the International Conference on Spoken Language Processing, Kobe, 1 January 1990, 825-828.
 McCune, K.M. (1985) The Internal Structure of Indonesian Roots. Number v. 2 in the Internal Structure of Indonesian Roots. Badan Penyelenggara Seri Nusa, Universitas Katolik Indonesia Atma Jaya, Jakarta.
 Mbrola, T. (2009) The MBROLA Home Page. http://tcts.fpms.ac.be/synthesis/mbrola/
 ITU (2001) ITU-T Recommendation P.862: Perceptual Evaluation of Speech Quality (PESQ): An Objective Method for End-to-End Speech Quality Assessment of Narrow-Band Telephone Networks and Speech Codecs. Technical Report, ITU.
 Rix, A.W., Beerends, J.G., Hollier, M.P. and Hekstra, A.P. (2001) Perceptual Evaluation of Speech Quality (PESQ)— A New Method for Speech Quality Assessment of Telephone Networks and Codecs. IEEE International Conference on Acoustics, Speech, and Signal Processing, Salt Lake City, 7-11 May 2001, 749-752.