1. Åström, K.J., and Wittenmark, B.: ‘Computer controlled systems’, 3rd(Prentice-Hall, Englewood Cliffs, NJ 1997)
2. Middleton, R.H., and Goodwin, G.C.: ‘Digital control and estimation’, (Prentice-Hall, Englewood Cliffs, NJ 1990)
3. Bauck, R.C.: ‘Servo loop compensation technique exhibiting improved bandwidth’, (US Patent 5,764,017)
4. Thaler, G.J., and Brown, R.G.: ‘Analysis and design of feedback control systems’, (McGraw-Hill, New York 1960)
5. Frequency response of sampled-data systems