Your professor has specified that you are to use scholarly (or primary research or peer-reviewed or refereed or academic) articles only in your paper. What does that mean?
Scholarly or primary research articles are peer-reviewed, which means that they have gone through the process of being read by reviewers or referees before being accepted for publication. When a scholar submits an article to a scholarly journal, the manuscript is sent to experts in that field to read and decide if the research is valid and the article should be published. Typically the reviewers indicate to the journal editors whether they think the article should be accepted, sent back for revisions, or rejected.
To decide whether an article is a primary research article, look for the following:
Caution: even though a journal may be peer-reviewed, not all the items in it will be. For instance, there might be editorials, book reviews, news reports, etc. Check for the parts of the article to be sure.
You can limit your search results to primary research, peer-reviewed or refereed articles in many databases. To search for scholarly articles in HOLLIS, type your keywords in the box at the top, and select Catalog&Articles from the choices that appear next. On the search results screen, look for the Show Only section on the right and click on Peer-reviewed articles. (Make sure to login in with your HarvardKey to get full-text of the articles that Harvard has purchased.)
Many of the databases that Harvard offers have similar features to limit to peer-reviewed or scholarly articles. For example in Academic Search Premier, click on the box for Scholarly (Peer Reviewed) Journals on the search screen.
Review articles are another great way to find scholarly primary research articles. Review articles are not considered "primary research", but they pull together primary research articles on a topic, summarize and analyze them. In Google Scholar, click on Review Articles at the left of the search results screen. Ask your professor whether review articles can be cited for an assignment.
A note about Google searching. A regular Google search turns up a broad variety of results, which can include scholarly articles but Google results also contain commercial and popular sources which may be misleading, outdated, etc. Use Google Scholar through the Harvard Library instead.
About Wikipedia. Wikipedia is not considered scholarly, and should not be cited, but it frequently includes references to scholarly articles. Before using those references for an assignment, double check by finding them in Hollis or a more specific subject database.
Still not sure about a source? Consult the course syllabus for guidance, contact your professor or teaching fellow, or use the Ask A Librarian service.