Authority

Does the source hold authority in their field?
Does the source cite others who have authority in the field?
Do they demonstrate (either in writing or through historical accomplishment) strong knowledge of the subject?

Bias

What is the point-of-view of the source?
Does the article openly frame its bias (share the author's point of view to explain their perspective)?
Is the source supported by organizations with a known interest in one side of the argument?

Context

When and where was this article published?
What else is the source publishing?
Check quotations and sources! Is everything being shared the way it was intended?
Is this serious or satire?