College professors will usually require some scholarly (also academic, peer-reviewed) sources.
Three things to look for:
- Was it written by experts? The authors are specialists in their field, list their educational background (e.g. PhD), and are usually affiliated with a university.
- Is it based on research? The findings are based on a study conducted by the authors, or on a review of other expert literature. There will *always* be a bibliography or works cited list of the research used.
- Who is the intended audience? Scholarly sources will use complex, expert language and be fairly lengthy. Most academic research is published in peer-reviewed journals or books, not freely available through Google.
Written by experts,
Written by journalists;
Based on research,
Based on opinions &
AKA: mass media,
Is this Article Scholarly? Use this checklist to be sure your sources are scholarly.
And check out this information timeline to understand when and how information is published.