1. Gregg, Richard E. “Some Hypotheses for the Study of the Psychology of Evidence,”. paper read at the 1964 SAA Convention.
2. Report SCRL, 4–67;McCroskey James C.,1967
3. Cathcart, Robert S. 1953. “An Experimental Study of the Relative Effectiveness of Selected Means of Handling Evidence in Speeches of Advocacy”. Northwestern University. unpublished Ph.D. dissertation
4. An experimental study of the relative effectiveness of four methods of presenting evidence∗
5. Bettinghaus, Erwin P. Jr. 1953. “The Relative Effect of the Use of Testimony in a Persuasive Speech upon the Attitudes of Listeners”. Bradley University. unpublished M.A. thesis