EzekielM.Methods of Correlation Analysis (First Edition). New York: John Wiley & Sons, 1930.
2.
GarrettH. E.Statistics in Psychology and Education (Fourth Edition). New York: Longmans, Green, 1953.
3.
SteadW. H.ShartleC. L., et al. Occupational Counseling Techniques. New York: American Book Company, 1940.
4.
WherryR. J. “A New Formula for Predicting the Shrinkage of the Coefficient of Multiple Correlation.” Annals of Mathematical Statistics, II (1931), 440–451.
