Wikipedia:Don't use external links where we'll want Wikipedia links

Don't use external links where we'll want Wikipedia links. Don't put in links like this (http://www.wikipedia.com) to external URLs linking text that we will want articles on Wikipedia about. Put external links in an "External Links" section at the end of the article. For example, if you're writing an article about Descartes and you know of a great article about rationalism online, don't link the word "rationalism" to that article. Simply wikify the word rationalism, and add an "External Links" section with an external link to the source (perhaps in both articles).

See debate.