1. J.A. Fischer and R. Koch, ?A highly linear CMOS buffer amplifier,?IEEE J. Solid-State Circuits, vol. SC-22, pp. 330?334, 1987.
2. J.H. Huijsing and D. Linebarger, ?Low-voltage operational amplifier with rail-to-rail input and output ranges,?IEEE J. Solid-State Circuits, vol. SC-20, pp. 1144?1150, 1985.
3. R. Hogervorst, R.J. Wiegerink, P.A.L. de Jong, L. Fonderie, R.F. Wassenaar, and J.H. Huijsing, ?CMOS low-voltage operational amplifiers with constant-g m rail-to-rail input stage,? inIEEE Int. Symp. Circuits and Systems, pp. 2876?2879, 1992.
4. R.F. Wassenaar, J. H. Huijsing, R.J. Wiegerink, R. Hogervorst, and J.P. Tero, ?Differential amplifier having rail-to-rail input capability and square-root current control,? U.S. Pat. Appl. Nr. 880.881, 1992.
5. E. Seevinck, W. de Jager, and P. Buitendijk, ?A low-distortion output stage with improved stability for monolithic power amplifiers,?IEEE J. Solid-State Circuits, vol. SC-23, pp. 794?801, 1988.