The aspect of this source that should make the reader question it’s credibility is:
Credibility refers to the authenticity of a piece of information. One of the characteristics of credible information is that it must be up-to-date.
So when talking about investment, the author must quote sources that are in tune with current trends. This factor was lacking in the citation because it is a 1964 source material.
Learn more about credibility here:
https://brainly.com/question/1279931
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