The persuasive effects of source credibility: Tests of cognitive response, Journal of Consumer Research
Two experiments are reported identifying the circumstances in which high credibility either facilitates, inhibits, or has no effect on the communicator's persuasiveness in relation to a less credible source. These data provide support for the cognitive response view of information processing and suggest the importance of message recipient's initial opinion as a determinant of persuasion.
Brian Sternthal, RubyRoy Dholakia, Clark Leavitt
Sternthal, Brian, RubyRoy Dholakia, and Clark Leavitt. 1978. The persuasive effects of source credibility: Tests of cognitive response. Journal of Consumer Research. 4(4): 252-260.