The institution that publishes material (university, business, government) has a share in determining how much faith you should put in that source, but how about the individual author(s)?
If you are using a scholarly journal article, it is relatively easy to find author credentials. Most scholarly journal articles give information about the author's academic career. The place where the information is given may vary. In scientific articles it is usually with or under the author's name.
In humanities articles it may be at the bottom of the first page, or at the end of the article.
Here are some possible ways to find out about an author:
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