Q. How do I search the citations of a specific author? I need to know what articles they've published.

Though not comprehensive, Google Scholar the largest collection of article citations through which to search. To search for articles by a specific author: 

1. Go to Google Scholar Advanced search. https://scholar.google.com/schhp?hl=en&as_sdt=0,44#d=gs_asd
2. In the Return articles authored by field, type in your authors name. 
3. You might also find some of teh other available options useful, such as Return articles dated between if you know when the author was actively publishing. 

You could also try the advanced search option in WorldCat. It may not provide as many articles to search through but it allows for a more precise search. Neither Google Scholar nor WorldCat would guarantee a comprehensive search of all articles by an author, but they are the closest that you can get. 

1. Go to WorldCat advanced https://www.worldcat.org/advancedsearch
2. Type the author in the author field
3. There are several fields under Narrow Your Search that you might find useful. If you just want article, use the Format pull down menu and Article. As you can see, you can also limit by date, language and content and they might all help. 

Keep in mind that there may be more than one author with the same name, so using any other options to narrow down if possible, may help. Good luck.