(The two books below are general references to A/D converters. The papers are about two step A/D conversion and 1.5b/stage pipelined conversion. The links should work from computers inside Columbia University. If they don't , visit http://ieeexplore.ieee.org/ and carry out an appropriate search)
Principles of Data Conversion System Design Behzad Razavi,
Wiley-IEEE, 1994.
Cmos Integrated Analog-To-Digital and Digital-To-Analog
Converters, Rudy J. Van Der Plassche, Kluwer Publishers, 2003