1. Bingham, C., Godfrey, M. D. andTukey, J. W. (1967) Modern techniques of power spectrum estimation.IEEE Trans.,AU-15, 56–66.
2. Brigham, E. O. (1974)The Fast Fourier Transform. Prentice-Hall, Englewood Cliffs, New Jersey.
3. Burrus, C. S. andParks, T. W. (1985)DFT/FFT and convolution algorithms—theory and implementation. John Wiley & Sons.
4. Coghlan, B. A., Taylor, M. G. andKing, D. H. (1974) On line analysis of Doppler-shift spectra by a new time compression analyser. InCardiovascular applications of ultrasound.Reneman, R. (Ed.), North Holland, Amsterdam, Chap. 5.
5. Gibbons, D. T., Evans, D. H., Barrie, W. W. andCosgriff, P. S. (1981) Real-time calculation of ultrasonic pulsatility index.Med. & Biol. Eng. & Comput.,19, 28–34.