1. M. Owen, SPC and Continuous Improvement, IFS Publications, Bedford, 1989.
2. J. S. Oakland and R. F. Followell, Statistical Process Control, Butterworth-Heinemann Ltd, Oxford, 1992.
3. J. Wang, R. G. Hannam, A. K. Kochhar and G. Vosniakos, ?A knowledge-based database approach for statistical quality control for part manufacturing?, Proceedings of the 1996 Chinese Automation Conference in the UK (CACUK'96), Oxford, pp. 99?104, 21?22 September, 1996.
4. Western Electric, Statistical Quality Control Handbook, AT&T, Princeton, 1956.
5. L. Walsh, R. Wurster and R. J. Kimber, Quality Management Handbook, Marcel Dekker Inc and ASQC Quality Press, New York, 1985.