While using the Kent Catalog you can use the limiters on the left hand of the screen to automatically remove all resources that are not Scholarly/Peer Reviewed sources by checking the box.
What is peer review?
Peer review is a process in which two or more experts in a field read an article and make suggestions for revisions before it is accepted for publication. To pass peer review, the article must give an original perspective on an important topic. It also must be thoroughly researched, logically argued, and well written. Most articles that are submitted to journals do not make it through peer review. The articles that do get published usually have extensive revisions. Most articles you see are the result of years of work by many people. To learn if a journal requires articles to be peer reviewed, locate journal’s information in the database you are using or the journal’s website.
Why should I use scholarly articles?
Scholarly articles are the most credible sources you can find because of the rigorous peer-review process. They are written by people who have studied this subject for many years and they have been reviewed by other people with similar experience. They are thoroughly researched, which means you can “mine” the article’s bibliography to find other sources that might be useful for your paper.
Information obtained from http://www.lonestar.edu/departments/tutoring/scholarly_sources.pdf