When considering a source, ask yourself some basic questions:

• What's the purpose of this source? Who is the intended audience?
• What kind of source is it? Is it a book, book chapter, journal article, magazine/news article, trade/professional article, report, etc.?
• Does this source fulfill the assignment requirements? If it is an article, is it peer-reviewed? 
• If it is a book, where was it published?
• Who is the author and what are their credentials?