1. Digital Signal Processing of Speech Signals, L. R. Rabiner & R. W. Schafer, Prentice-Hall Inc, 1978.
2. Speech Communication, Human and Machine, D. O'Shaugnessy, Addison-Wesley, 1987.
3. Signal and Systems<\I>, A. V. Oppenhein & A. S. Wilsky, Prentice-Hall Inc, 1983.