1. Darley, J. G. 1941.Clinical Aspects of Interpretation of the Strong Test, 72New York: Psychological Corp.
2. Ford, A. 1931.A Scientific Approach to Labor Problems, 446New York: McGraw-Hill.
3. Kaback, G. R. 1946.Vocational Personalities, 114New York: Teach. Coll., Columbia Univ.