hi, which book says the output pole will go to infinity? I have never readed that statements!

Bharat,

  The original explanation was a little simplified, there is a detailed discussion
in the following sources,

James E. Solomon, “The Monolithic Op Amp: A Tutorial Study,” IEEE Journal
of Solid-State Circuits, vol. sc-9, pp 314-332, Dec 1974

Grey, Hurst, Lewis, and Meyer, "Analysis and Design of Analog Integrated
Circuits", fourth edition, page 639-644

When analyzing ampliers, the Miller Approximation allows designers to estimate the
effect of an impedance connect across the amplifier as a capacitor, zA, at the input
node. As a result the pole due the input node of the second stage is reduced, moves
towards zero and the pole at the output of the second stage moves towards infinity.
Since the frequency difference of the two poles is increased, the poles are said to
be split.

For the reason that the second pole moves towards infinity, you should review the
derivations in the references above. Just remeber that C[zA] is not the only terms
in the expression for the second pole, rather C cancels some nasty terms in the second
pole and thus the pole moves towards infinity.

                                                                                 Best Regards,

                                                                                     Sheldon