8Abdel-khalik, A.R., D.Snowball, and J.H. Wragge. The effects of certain internal audit variables on the planning of external audit programs. The Accounting Review, April (1983): 215-227.
9Barrett. M. J. and V.Z.Brink.1980.Evaluating Internal/External Audit Services and Relationships. Ahamonte Springs, FL: The Institute of Internal Auditors, Inc.
10Berry, L. E.1984. Coordinating Total Audit Coverage: Trends and Practices. Altamonte Springs, FL: The Institute of Internal Auditors, Inc.
