Citation Analysis or citation tracking is a way to see the impact of an article in its field. Also, it's a great way to use a "landmark" or influential article to find more recent, related articles that cite the landmark article. Search in Google Scholar or Web of Science to see if your source has been cited by others!
Google Scholar allows you to use the Google search engine to look for scholarly articles instead of browsing the entire web. Look in the bottom left of each result to see the number of times the article has been cited by others.