Generally, there are a number of elements to consider when evaluating the quality and scholarliness of a source. During your literature review, you want to make sure you only include credible, scholarly sources. Use the following guidelines to help you in your evaluation.
Also listed are a few websites that offer criteria on how to evaluate your sources.
Authority
What are the author's credentials?
Can you identify their institutional affiliations?
What is the author's expertise on the subject?
Currency
When was the source published?
Is it outdated?
Does it meet the time needs for your topic?
Documentation
Does the author cite credible, authoritative sources?
Is there evidence of scholarly research?
Do they properly cite their sources?
Intended Audience
Who is the intended audience? Scholars? Researchers? General audience?
Objective / Purpose
What is the author's goal in writing it? To entertain? To inform? To influence?
How objective is the source?
Relevancy
Is it relevant to your topic?
Does it provide any new information about your topic?
