1. Toumazou, C., Lidgey, F.J., Haigh, D.G., Analogue IC design: the current-mode approach, (Peter Peregrinus 1990)
2. PMI OP260 data sheet
3. Analogue Devices AD844 data sheet
4. Allen, P.E., and Holberg, D.R.: CMOS analog circuit design, (HRW, Inc., Orlando, Florida 1987)