[1] V. Ivanov, R. Brederlow and J. Gerber, "An Ultra-Low Power Bandgap Operational at Supply From 0.75 V," in IEEE Journal of Solid-State Circuits, vol. 47, no. 7, pp. 1515- 1523, July 2012.

[2] George Raikos and Spyridon Vlassis, “0.8 V bulk-driven operational amplifier,” in Analog Integrated Circuits and Signal Processing, June 2010, Volume 63, Issue 3, pp 425– 432.

[3] J. M. Carrillo, G. Torelli, R. Perez-Aloe Valverde and J. F. Duque-Carrillo, "1-V Rail-to-Rail CMOS Op-Amp With Improved Bulk-Driven Input Stage," in IEEE Journal of Solid-State Circuits, vol. 42, no. 3, pp. 508-517, March 2007.

[4] T. Stockstad and H. Yoshizawa, "A 0.9-V 0.5-μA rail-torail CMOS operational amplifier," in IEEE Journal of SolidState Circuits, vol. 37, no. 3, pp. 286-292, Mar 2002.

[5] F.Kacar, Abdullah Yesil and Abbas Noori, “New CMOS Realization of Voltage Differencing Buffered Amplifier and Its Biquad Filter Applications” Radio Engineering, Vol. 21, No. 1, April 2012, pp 333-339.

[6] P.E. Allen and D.R. Holberg, “CMOS Analog Circuit Design” Oxford University Press, 2nd edition.

[7] B. Razavi, “Design of Analog CMOS Integrated Circuits,” Tata McGraw-Hill, 2012.

[8] P.R Gray and R.G Mayer, “Analysis and Design of Analog Integrated Circuits”. New York: Wiley, 2011.