1. Barker, I., Alderson, J., Lydon, M. andFranks, C. I. (1985) Cardiovascular effects of spinal subarachnoid anaesthesia.Anaesthesia,40, 533–536.
2. Caprihan, A., Davies, J. G., Greene, E. R., Loeppky, J. A. andEldridge, M. W. (1982) Waveform analysis of Doppler ultrasound signals by a microcomputer.IEEE Trans.,BME-29, 138–142.
3. Corbett, J. L., Debarge, O., Frankel, H. L., Mathias, C. J., (1975) Cardiovascular responses in tetraplegia man to muscle plasm, bladder percussion, and lead up tilt,Clinical & Experimental Pharmacol. & Physiol., Suppl. 2, 189–193.
4. Cross, G., andLight, L. H. (1974) Non-invasive intra-thoracic blood velocity measurement in the assessment of cardiovascular function.Biomed. Eng.,99, 464–471.
5. D'Alessio, T. (1985) ‘Objective’ algorithm for maximum frequency estimation in Doppler spectral analysers.Med. & Biol. Eng. & Comput.,23, 63–68.