The source of the information.
Who is the author/publisher/sponsor?
What are the author's credentials or organizational affiliations?
Is the author qualified to write about this topic or is an expert on this topic?
Is there contact information or an email address listed for the author/publisher?
Does the URL reveal anything about the source?
.com = commercial
.org = organization
.edu = education
.gov = government
Typically you will find the author's name either underneath the title of the article; the publisher or sponsor information at top or bottom of a webpage.
You might also look for an "About" page, this will give you information on the purpose for the website and information on the authors/sponsors/publishers/contributors to the website.