Most research papers require the use of peer-reviewed sources, and for good reason: peer-reviewed journals are generally more thorough and objective than websites, magazines, and newspapers. (Learn more about scholarly, peer-reviewed sources here.)
If your assignment calls for peer-reviewed sources and you've found a non-peer-reviewed source that seems essential, ask your professor about it. They might agree! Sometimes, non-peer-reviewed sources are used as examples, or in an introductory literature review.
If you're tempted to use a non-peer-reviewed source because you can't find enough peer-reviewed sources, talk with a librarian. Librarians can help you find more sources by choosing different search terms, trying different databases, and refining research topics. Find librarian contact information at Ask Us.
