This post is about something that doesn't come up too often in law schools now: using Shepard's Citations in print. Here are a couple of places with quick primers on how to use these red books.
U. Delaware has a decent guide, with a picture, that goes over the basics here. And this is pretty similar to what you'll see in Legal Research in a Nutshell (on Reserve and behind the Ref. desk in our library).
Ernster, the Virtual Library Cat
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