1. Catell, R. B., and Eber, H. W. (1957).Handbook for the Sixteen Personality Factor Questionnaire. Institute for Personality and Abiltiy Testing, Champaign, Ill.
2. Costanzo, F. S., Markel, N. N., and Costanzo, P. R. (1969). Voice quality, profile and perceived emotion.J. Counseling Psychol. 16: 267?270.
3. Ebel, R. L. (1951). Estimation of the reliability of ratings.Psychometrika 16 407?424.
4. Guilford, J. P. (1954).Psychometric Methods. McGraw-Hill, New York.
5. Markel, N. N. (1965). The reliability of coding paralanguage: Pitch, loudness, and tempo.J. Verbal Learn. Verb. Behav. 4: 406.