Can't see the need for a join, as Articles only has a field Article that is in the ArticleInfo table.
However, if there are more fields there then:
Left Join (Articles)
Article, // I am assuming Article is the only similarly named field on the two tables
RESIDENT ArticleInfo: // This is assuming you loaded Article Info into a Qlikview table first. If you don't want to then this RESIDENT line could be an SQL statement instead
Be careful that the Article only appears once in both tables, to ensure you don't get a cartesian join. You can do this by testing the number of rows of the Articles table (hovering over it's header in the Table Viewer will show what this is) before and after your join.