1. Christensen, P. R.,Guilford, J . P., Merrifield, P. R. & Wilson, R. C. Alternate Uses. Beverly Hills, California: Sheridan Psychological Services, 1960.
2. Cronbach, L. J. Coefficient alpha and the internal structure of tests. Psychometrika, 195 1, 16, 297-334.
3. Glass, G. V. & Stanley, J. C. Statistical methods in education andpsychology. Englewood Cliffs, New Jersey: Prentice-Hall, 1970.
4. Guilford, J. P. Traits of creativity. In H. Anderson (Ed.), Crearivity and its cultivation. New York: Harper, 1959.
5. Kerlinger, R. & Pedhazur, E. Multiple regression in behavioral research. New York: Holt, Rinehart & Winston, 1973.