There are now several books in print that the CISA (Certified Information Systems Auditor) candidate can use as a study aid for the CISA exam.
CISA Certified Information Systems Auditor All-In-One Study Guide, 3rd ed
by Peter H. Gregory, CISA, CISM, CIPM, CRISC, QSA, CISSP, CCISO
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CISA: Certified Information Systems Auditor Study Guide, 2nd edition
by David Cannon
CISA: Certified Information Systems Auditor Study Guide by David L. Cannon, Timothy S. Bergmann, and Brady Pamplin
CISA Exam Cram 2 : Certified Information Systems Auditor by Allen Keele and Keith Mortier
CISA Exam Prep: Certified Information Systems Auditor (ACM Press) by Michael Gregg
IT AUDIT: A Practical Guide To the CISA Exam by Trony Clifton
Peter H. Gregory 
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