Before you can add a link to a Wiki article – you must know the exact name of the Wiki article to which you are linking.

What to do

With the article open in edit-mode :

1. Scroll to the place you want the link
2. Enter '[[article-name]]'  where 'article-name' is the name of a Wiki article
3. Click the Save page button – the link is added to the Wiki article

Example - article name as link-text

... are setting ArticleName to ensure ...

Created by :

 ... are setting [[ArticleName]] to ensure ... 

Example - alternate link-text

... are setting Article Name to ensure ...

Created by :

 ... are setting [[ArticleName|Article Name]] to ensure ...