Quality Function Deployment by L. Cohen. 368 pages. Copyright 1995. ISBN 0201633302. Published by Prentice-Hall-PTR.
Statistical Thinking: Improving Business Performance by R. Hoerl and R. Snee. 544 pages. Copyright 2001. ISBN 0534381588. Published by Duxbury Press.
Design for Six Sigma Statistics by Andrew Sleeper. 854 pages. Copyright 2005. ISBN 0071451625. Published by McGraw-Hill Professional.