Hi, all: I think these papers is useful for me to design opa:

1.R.Hogervorst et al., "CMOS low-voltage operational amplifiers with constant-gm rail-to-rail input stage," Analog Integrated Circ. Signal Proc., vol. 5, no.2, pp. 135-146, Mar. 1994

2.R.G.H.Eschauzier and J.H.Huijsing, "an operational amplifier with multipath Miller zero cancellation for RHP zero removal," in Proc. ESSCIRC.(Seville, Spain), Sept. 1993, pp. 122-125

my email: wjx197733@126.com