One of the easiest ways to find out who else has cited the article you're interested in is to use the "Cited By" tool in Google Scholar.
Search in Google Scholar for the article you want to know more about. You can access Google Scholar from anywhere with any web browser by either keyword searching “Google Scholar” or using the following URL: scholar.google.com
Type the title of the article in quotes into the search bar and click "Search":
Locate your article in the search results, and look for the "Cited By" link underneath your article. This will tell you approximately how many times the articles has been cited by other scholars, which gives you a sense of how important the article is:
Click on the "Cited By" link for a list of the articles and sources that cited the article you are interested in: