UN documents often have a unique document symbol:
For more information about interpreting document symbols, see theDag Hammarskjöld Library's Document Symbols Research Guide.
Many older UN publications are available by searching GEORGE for "United Nations" as an author and looking for individually cataloged titles. If you are looking for a resolution from the GA or Security Council, the following resources may be helpful:
The UN was preceded by the League of Nations (1920-1946). Information about the League:
Lauinger also has an extensive set of League documents in microfilm.
Can't find a UN document at GU? Try the Library of Congress, the closest official UN Depository Library.
The United Nations Information Centre in Washington also has copies of official records.
The Dag Hammarskjöld Library in New York has the most extensive collection of UN documents in the nation (and possibly the world). If you're trying to track down an elusive UN document, try their AskDAG service.