1. Vodovnik, L., Crochetiere, W. J., and Reswick, J. B. (1967) Control of skeletal joint by electrical stimulation of antagonists. Med. Biol. Eng., 5, 97–109.
2. Chizeck, H.J. (1992) Adaptive and nonlinear control methods for neural prostheses. In: Neural Prostheses, eds: Stein R.B., Peckham P.H. & Popovic D.B., Oxford University Press, p. 298.
3. Ewins, D. J., Taylor, P.N., and Swain, I. D. A functional closed-loop sit/stand system for mid/low thoracic paraplegics. In: Advances in External Control of Human Extremities, X, ed: Popovic, Nauka, Belgrade, 261–264, 1990.
4. Khang, G. and Zajac, F. E., (1989) Paraplegic standing controlled by functional neuromuscular stimulation: part I - Computer model and control system design. IEEE Trans. Biomed. Eng., 36, 873–894.
5. Bajzek, T. J. and Jaeger, R. J. (1987) Characterisation and control of muscle response to electrical stimulation. An. Biomed. Eng., 15, 485–501.