Google Scholar provides a simple and broad way to search for scholarly literature. You can search across many disciplines and sources: articles, theses, books, abstracts and court opinions, from academic publishers, professional societies, online repositories, universities, and other web sites.
Navigate to Google Scholar - make sure you are actually in Google Scholar, not just a normal Google search.
Select Advanced Scholar Search by clicking the arrow on the right-hand side of the search field.
In Advanced Scholar Search, enter information about the article. For example, we can search for the title "Quantum Measurement" in the "with all of the words" search field. Then, we can enter A.J. Leggett as the author in the field "Return Articles authored by."
In the search results there will be a "Cited by" link beneath the article citation that shows the number of sources Google Scholar found citing the article.
Clicking on the "Cited by" link gives a list of articles that have cited the article.
Note: Google Scholar will likely produce more cited references than either Web of Science or Scopus, but some of these may be duplicates. Google does not provide a complete list of all the publications it indexes, so it is difficult to know if Google Scholar provides comprehensive citation counts.