Maybe I'm reading between the lines too much, but this seems to be creating a problem by being overly-general.<p>Certainly, if you discuss or analyse an article or document which is available online, link to it for the benefit of your audience (and the original author). (Exceptions like discussing a hate crimes page and not wanting to give it google-juice are fine, just let us know you're doing it.)<p>But the OP seems to blur this with other sources not already available on the web (or, presumably for example, behind a paywall). Are you asking for these to be uploaded, which is potentially copyright infringement and at least may go against the original author's intent?<p>If I review a book, do you need the primary source included?