Gulliksen, H. Theory of Mental Tests. New York: Wiley, 1950. Swineford, F.Analysis of a Personality Trait . Journal of Educational Psychology, 1941 , 32, 438-444.
2.
Torrance, E. P. and Ziller, R. C.Risk and Life Experience: Development of a Scale for Measuring Risk-taking Tendencies. Research Report AFPTRC-TN-57-23, ASTIA Document No. 098926. Lackland Air Force Base, Texas: Air Force Personnel and Training Research Center; February 1957.