HOWTO – Create autolinks to source in post

Hi,
how it is possible to use an auto-link to the source-post in the local article (textarea not title), like e.g. here:

This post is a reprint of a post by JoeKudda that originally appeared at Game of the Week. Source: http://www.lax247.com/