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University of Utah Library Guides

Call numbers: Home

An overview of the call numbers and classification schemes you might encounter at the Marriott Library and where to find them.

Introduction and Overview

In a library, a call number is a unique combination of letters and numbers that indicates an item's location.  In the most simple of systems a library could assign each item a sequential number when it is acquired and store them in that order, but in such a system you could not count on there being any relationship other than proximity between two adjacent items.  All library classification systems attempt to impose a logical order on physical items in the collection so that like items are grouped together (by format, subject, language, author, publisher or other attribute, either alone or in combination).

While most of our circulating collections are classified using the Library of Congress (LC) classification, there are also substantial portions that use other schemes:  Dewey Decimal Classification (DDC or just Dewey), Superintendent of Documents (SuDocs) classification, National Library of Medicine (NLM) classification [in the Marriott Library books with NLM call numbers are only found in the ARC], and United Nations (UN) documents classification.  As you will see below, LC, SuDocs, NLM and UN call numbers all start with one or more letters, and often based only on that beginning you can identify the system in question.  For instance:

  • LC call numbers never start with the letters I, O, W, X or Y; the class (the beginning of the call number) can consist of one, two or (very rarely) three letters
  • NLM call numbers always start with either Q or W (two of the letters not used in LC), and the class can consist of one, two or three letters
  • SuDocs call numbers always start with a mnemonic for the issuing agency (Congress being the only exception), which can be one, two, three or four letters
  • UN document call numbers (called symbols) are even more consistently mnemonic than SuDocs call numbers

Dewey call numbers, by contrast, start with a three-digit number, either a whole number or one followed by a decimal point and one, two, three or more digits.  This chart shows correspondence between Dewey and LC.

Superintendent of Documents

A -- Agriculture

AE -- National Archives and Records Administration

B -- Broadcasting Board of Governors

C -- Commerce Department

CC -- Federal Communications Commission

CR -- Civil Rights Commission

D -- Defense Department

E -- Energy Department

ED -- Education Department

EP -- Environmental Protection Agency

FA -- Fine Arts Commission

FCA -- Farm Credit Administration

FHF -- Federal Housing Finance Board

FM -- Federal Mediation and Conciliation Service

FMC -- Federal Maritime Commission

FR -- Federal Reserve System Board ofr Governors

FT -- Federal Trade Commission

FTZ -- Foreign-Trade Zones Board

GA -- Government Accountability Office

GP -- Government Printing Office

GS -- General Services Administration

HE -- Health and Human Services Department

HH -- Housing and Urban Development Department

HS -- Homeland Security

I -- Interior Department

IC -- Interstate Commerce Commission

ID -- US Agency for International Development

ITC -- International Trade Commission

J -- Justice Department

JU -- Judiciary

L -- Labor Department

LC -- Library of Congress

LR -- National Labor Relations Board

MS -- Merit Systems Protection Board

NAS -- National Aeronautics

NC -- National Capital Planning Commission

NCU -- National Credit Union Administration

NF -- National Foundation on the Arts and the Humanities

NMB -- National Mediation Board

NS -- National Science Foundation

OP -- Overseas Private Investment Corporation

P -- United States Postal Service

PE -- Peace Corps

PM -- Personnel Management Office

PR -- President of the United States

PREX -- Executive Office of the President

PRVP -- Vice President of the United States

RR -- Railroad Retirement Board

S -- State Department

SBA -- Small Business Adminstration

SE -- Securities and Exchange Commission

SI -- Smithsonian Institution

SSA -- Social Security Administration

T -- Treasury Department

TD -- Transportation Department

TDA -- US Trade and Development Agency

VA -- Veterans Affairs Department

X and Y -- Congress

United Nations

First components of UN call numbers (called symbols) indicate organs to which documents were submitted or that issued the document:

A -- General Assembly

CRC/C -- Committee on the Rights of the Child

DP -- United Nations Development Programme

E -- Economic and Social Council

S -- Security Council

ST -- Secretariat

TD -- United Nations Conference on Trade and Development

UNEP -- United Nations Environment Programme

Second components indicate types of subsidiary bodies:

/AC -- Ad Hoc Committee

/C -- Standing, Permanent or Main Committee

/CN -- Commission

/CONF -- Conference

/GC -- Governing Council

/PC -- Preparatory Committee

/SC -- Subcommittee

/Sub -- Subcommission

/WG -- Working Group

or the nature of the document:

/CRP -- Conference Room Paper

/INF -- Information Series (e.g., Lists of Participants)

/L -- Limited Distribution (Generally Draft Documents)

/NGO -- Statements by Non-Governmental Organizations

/PET -- Petitions

/PRST -- Statements by the President of the Security Council

/PV -- Verbatim Records of Meetings (i.e., Procès Verbaux)

/R -- Restricted Distribution or Access (Unless Subsequently Derestricted)

/RES -- Resolutions

/SR -- Summary Records of Meetings

/WP -- Working Papers

Final components reflect modifications to the original text:

/Add -- Addendum

/Amend. -- Amendment

/Corr -- Corrigendum

/Rev -- Revision (Replacing Texts Previously Issued)

/Summary -- Summarized Version

/* -- Reissuance of a Document for Technical Reasons

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