The broadest coverage of the widest variety of legal topics are found in Legal Encyclopedias.
When you don’t know which type of secondary source to use,
There are two National Legal Encyclopedias:
Corpus Juis Secundom (CJS)
CJS is more scholarly and historical
American Jurisprudence 2d (AmJur)
AmJur is more practical
Many states also have Legal Encyclopedias. Illinois has two:
Illinois Law & Practice KFI 1265 .I442X
Illinois Jurisprudence KFI 1230.5 .L38
They are found in the Illinois Alcove near the Reference Desk.
PRINT: AM JUR 2d is found on the shelves in the middle of the main Reading Room
ONLINE: Lexis, or Westlaw
Legal Encyclopedias sometimes use "hidebound" (old) terms, so it's always a good idea to begin in the INDEX.
Example: when you look up Sale of Real Property, you will be directed to a topic called Vendor & Purchaser.
Sale of Real Property, Vendor & Purchaser This Index
Vendor & Purchaser
This Index = find the index volume that covers the letter V and look there for Vendor & Purchaser
above = stay in this listing, but look for a sub-topc above (supra)
below = stay in this listing, but look for a sub-topic below (infra)
Legal Encyclopedias are updated with annual Pocket Parts.
Be sure to check the same Topic and Section Number in the pocket part insert in the back of the volume.
Legal Research in a Nutshell, pp. 32-36.