IncludeArticle is an Extension for MediaWiki. When editing a wiki article, it allows the inclusion of another article using the following syntax:
<include article="MyArticle" />
The value of article should be the title of the article you wish to include.
Article access errors can be output to the page using the showerror parameter:
<include article="MyArticle" showerror="true" />
Important: MediaWiki already has similar functionality built-in. Please refer to http://www.mediawiki.org/wiki/Transclusion
Simply copy the IncludeArticle folder to your Mediawiki extensions folder.