Almost all reputable articles will give contact addresses and invite further discussion. Email the author for further info. Next check that the article is correctly dated. The version number or last updated date should be prominently displayed. Be wary of some old dates.
Good info contains citations to original sources that are solid and reliable.
Good info includes a bibliography. Most common on the web is info that pretends to be objective but contains a hidden agenda, a conflict of interest. It is intended to be particularly useful to librarians and others who are selecting sites to include in an information resource guide, or informing users as to the qualities they should use in evaluating Internet information. Feedback and suggestions of other sites for inclusion are welcomed by the site maintainer, Alastair Smith. Now imagine that your grocer is so accommodating that he lets anyone in town print up a magazine and put it in the magazine section.