Citation Chaining: One of the most underused techniques when searching for articles is citation chaining. There are two ways in which you can follow citation chains.
Forward Chaining: This method works best when you have an article that is highly relevant to your question. The older the article the more likely it is to have been cited by others. SCOPUS and Google Scholar allow you to see how many times an article has been cited and by whom. This allows you to see who built upon the work of the original article.
Backward Chaining: This method works with any article. By consulting the bibliography of an article you can discover past works that you should review and cite in your own work. It is important to pay attention to both the titles of the works cited and why they are cited in the text because some titles may not look relevant to your own work, but may be cited in a way that indicates they are highly relevant.