1. ASQC. (1987a). Guide for reducing quality costs (2nd ed.). Milwaukee: ASQC.
2. ASQC. (1987b). Guide for managing supplier quality costs. Milwaukee: ASQC.
3. Bhat, K. S. (2002). Total quality management: Text and cases. Mumbai: Himalaya Publishing House.
4. Borror, C. M. (2008). The certified quality engineer handbook (3rd ed., pp. 109–110). Milwaukee: ASQ Quality Press.
5. British Standards Institute. (1990). BS 4163: Guide to the economics of quality: Part 2 prevention, appraisal, failure model. London: BSI.