This is a field of the Media Form. That form is included in topics that describe media, such as newspaper articles, video, pictures, TV clips, etc. that may be of interest.
The media type LinkedArticle means that a Media Link is provided in the form, so that users can click to the original article. It may also be the case that the article is also copied into the body of the media topic, so that it can be read directly or so that an abstract can be provided to the user.
A Media Link should be the complete URL of the resource, such as
-- Raymond Lutz - 05 Jul 2007