References
Books
- Duncan, A. J., Quality Control and Industrial Statistics, 3rd ed., Richard D. Irwin, Inc., Homewood, Ill., 1965, p. 94.
- Kendall, M. G., and Stuart, A., The Advanced Theory of Statistics, Vol. 1, 2nd ed., Hafner Publishing Company, New York, N. Y. 1963, pp. 232–265.