Evaluating the sources you find is a crucial step in the process of scholarly research. The questions you ask about books, periodical articles, or multimedia sources are similar whether you're looking at a citation to the item or have the item in hand.
Read: Distinguishing Scholarly from Non-Scholarly Periodicals: A Checklist of Criteria.
Shows how to evaluate periodicals by looking at their format, intended audience, and appearance.
Is there useful and valid information in non-scholarly sources, such as blogs, newspapers, and magazines? Of course!
This guide will help guide you interrogate sources for accuracy, authority, and point of view:
Evaluating News Sources -- * ever more critically important *