Once you have found a full source (online or print), use the CRAAP Test to determine if you should use it.
When was the information published or updated? Are the references to other sources up to date? Does currency matter for your topic?
Is this source relevant to your research question? Does the source meet the requirements of the assignment? Is the information too technical or too simple? Who is the intended audience? Does it add to your knowledge of the topic?
Who is the author? Is the author part of an educational institution or an organization? Can you find information about the author on the internet or with other resources? How often is this author cited? The author may be an individual or an organization.
Is this information correct and reliable? Are there spelling or grammar errors? Was the information reviewed or edited before it was published? What are other authors writing about the topic?
What is the purpose of the information? Is it designed to sway your opinion? Does it project a bias? Are there other points of view presented?