Page Rank is the original algorithm for determining the importance of a web page that catapulted Google into the search engine stratosphere. A key concept in the algorithm is that a page is more important if many other pages link to it, particularly if the linking pages themselves are of high importance. That core idea was not completely new; citation analysis was actually pioneered to help judge the impact of academic articles and authors.
Where there is money, or kudos, to be gained by artificially inflating the importance of a web page or article there will also be people who attempt to do just that. Black hat SEO (Search Engine Optimization) is the term for techniques that involve gaining increased rank by nefarious (sometimes illegal) means. Here is a particularly ‘meta’ example… a link, placed by hacking the citation list in an academic journal, to improve the Google ranking for a site selling Ugg Boots.
I don’t think this is what Larry Page had in mind when he drew upon citation analysis to develop Google’s original ranking algorithm.