These do not cost the library much. You can then pull up the complete citations yourself. Three datatabases are especially amazing, SciSearch, Arts and Humanities Search, and SocSciSearch. Find a good article, a year or more old. The above citation indexes will tell the new articles that are citing it.
Normal research involves checking an article's footnotes to find relevant older material.
Citation research is just the reverse. It finds an old article and checks to see what new articles are including it in their footnotes. One can also find an authority and find what new articles cited that authority in their footnotes. After you get a new article, perhaps dated 2000 or 2001, on your topic you can again check the footnotes for older articles. Click Your Dictionary .