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Government Information

This is a guide to government resources that are commonly used in research.

About Sudoc

Federal documents are arranged by the U.S. Superintendent of Documents (SuDocs) Classification System based on the issuing government agency.

For example, the SuDocs number for the Department of Justice begins with "J" and "ED" identifies documents from the Department of Education.

The FDLP has more information on their SuDoc webpage. Michigan State University has an excellent guide on using SuDoc Classification that also explains in plain language how the numbers are created. 

How To Read a SuDoc Number

How to read a Federal SuDocs call number:

Federally produced documents are classified by a SuDocs--or Superintendent of Documents--call number. This number can be short and sweet, or long and meandering. You will find the call numbers depicted horizontally (in the above examples) in the library's online catalog and depicted vertically (as you will see in the quiz below) on the actual item's call number label. Taking the call number one step at a time, they are categorized and filed alphabetically by the agency that produces the document. This differs from the Dewey Decimal system or the Library of Congress / LC system (both used by Booth Library) which are both subject-oriented classification systems. Another characteristic of SuDocs call numbers is that they include punctuation marks not seen in Dewey or LC.

[1.] the class stem includes all letters and numbers before the :colon. The class stem tells you who published the document, for example, 'A' for the Department of Agriculture, 'C' for the Commerce Department or 'D' for Defense Department.

[2.] the book number includes everything after the :colon.  The book number details information about whether it is a monograph (a one-time publication) or part of a series, and the publication date or the year of congress it was developed.

This is a "quick and dirty" translation you need to find any Government Document (GovDoc). If you're interested in further details, take a look at the Superintendent of Documents Classification System which goes into greater length on SuDocs call numbers. If you're interested in more rules and regulations, the latest edition of the GPO Classification Manual has five chapters and 102 pages of classification explanation.

1) Before the colon :  includes the originating agency abbreviation and other identifying information up to and including a colon (which acts as a stopping point, a period, or end of the sentence).

A document entitled The Future of Journalism with the call number Y 4 .C73/7:S.HRG.111-428  
Class Y indicates it is a document produced by Congress. Y 4 means the document is a House and Senate Congressional Committee Hearing.
.C73/7: means that a specific Senate subcommittee, the "Committee on Commerce, Science and Transportation," is involved in the publishing of this document.

2) After the colon : all numbers and letters following the colon are the unique book number identifying each published item, a series part, and the year or # of congress during which the item was published.


For the title Obamacare Implementation: Sticker Shock of Increased Premiums for Healthcare Coverage with a call number of Y 4 .G74/7:113-78.

Before the colon
Y 4 is the issuing agency--the House and Senate Committee hearings
.G74/7: is a subcommittee, the Committee on Oversight and Government Reform          

After the colon, the publication date is expressed as a year (or the number of the Congressional session under which it was created); and a series number.
113 denotes the one hundred thirteenth Congress during which the hearing originated
-78 is the series number (which would be followed by 113-79, 113-80, etc., if more hearings in the same series were published during the 113th congress)‚Äč.*

*Content from the Government Documents SuDoc Classification page

SuDoc Symbols

logo for the FDLP


Below is a table of all of the alphabetical symbols for the SuDoc classification system. 

Click on the icon to be taken to the FDLP SuDoc Classification site.