Government Publications

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U.S. Depository Library
Government Classifications Systems:
U.S. Superintendent of Documents Classification system (SuDoc)
The Government Publications section uses the SuDoc classification system to arrange our collection. This system is designed to place together all of those publications published by the same government agency. The initial letter or letters of the call number signify the government agency responsible for publishing that document. All letters and combinations of letters are used except for the letter Z. The letters X and Y are used for Congressional publications.
  • I =Department of the Interior
The numbers following the letter(s) indicate the sub-agency within the larger agency.

Sub-agencies within the Department of the Interior

  • I 19. =U.S. Geological Survey
  • I 28. =Bureau of Mines
  • I 29. =National Park Service
A period follows these numbers. THIS IS NOT A DECIMAL POINT. The number following the period needs to be read as a WHOLE NUMBER. This whole number designates the type of publication.

Selected types of publications within the U.S. Geological Survey

  • I 19.1: =U.S. Geological Survey Annual Reports
  • I 19.3: =U.S. Geological Survey Bulletins
  • I 19.16: =U.S. Geological Survey Professional Papers
  • I 19.76: =U.S. Geological Survey Open Files Reports
Sometimes there are related series to already existing series. In order to have these related series filed together, a slash is used to indicate the relationship.

Selected U.S. Geological Survey related publications

  • I 19.3: =U.S. Geological Survey Bulletins
  • I 19.3/3: =U.S. Geological Survey. Water Resources Bulletins
Following the colon, there can be letters and numbers which usually indicate the title of the document or a designation for a year (1989=989 in this system).

Filing of U.S. government publications

The key phrase when looking for U.S. government publications in our collection is the "nothing before something" rule. For example, Interior publications (I) would file before International Trade Commission publications (ITC). Another crucial item is that the period is NOT A DECIMAL POINT and the numbers following the period need to be read a whole numbers. Finally, when looking for publications which differ in their classification number after the colon, the rule is DATE before LETTER before NUMBER before WORD. However, this does not apply to parts, volumes, sections, or revisions of the same publication. Below is a list of properly ordered U.S. government publications.

  • I 1.98:T 68
  • I 1.98:T 68/decision
  • I 1.98:T 68/draft
  • I 19.1:989
  • I 19.1:991
  • I 19.2:M 86
  • I 19.2:M 86/980
  • I 19.2:M 86/2
  • I 19.2:M 86/2/990
  • I 19.3:1134
  • I 19.3/3:657
  • I 19.14:990
  • I 19.14/4:987/5
  • I 19.14/4:987/6
The Colorado State Publications Classification system

The Colorado classification system used to order this collection is similar to the U.S. Superintendent of Documents Classification system. In the Colorado State Publications Classification system, the initial letters of the call number indicate the issuing agency. The numbers following the initial letters indicate the primary division while numbers following a slash designate any further subdivision of the agency.

Colorado Department of Natural Resources and selected sub-agencies within the Department

  • NR =all of the agencies and sub-agencies within the Department of Natural Resources
  • NR 1. =Colorado. Dept. of Natural Resources
  • NR 2. =Colorado. Soil Conservation Board
  • NR 5. =Colorado. Division of Water Resources
  • NR 12. =Colorado. Division of Minerals and Geology
  • NR 12/20. =Colorado Geological Survey
  • NR 12/40. =Colorado. Office of Mined Land Reclamation
  • NR 12/60. =Colorado. Office of Active and Inactive Mines

A period follows these numbers. THIS IS NOT A DECIMAL POINT. The number following the period needs to be read as a WHOLE NUMBER. This whole number designates the type of publication.

Selected types of publications within the Colorado Department of Natural Resources

  • NR 1.1 =Colorado. Dept. of Natural Resources Annual Reports (usually followed by a date)
  • NR 1.2 =Colorado. Dept. of Natural Resources General Publications (usually followed by a cutter number)
  • NR 1.3 =Colorado. Dept. of Natural Resources Bulletins (usually numbered)
Filing of Colorado state publications

The Colorado state publications are filed by agency first, followed by the sub-agencies within the larger agency. Therefore a period, which separates the agency from the type of publication, precedes the slash which designates a sub-agency (i.e. NR 1.3 precedes NR 1/2). Colorado state publications also follow the "nothing before something" and the DATE before LETTER before NUMBER before WORD rules. Below is a list of properly ordered Colorado state publications.

  • NR 1.1/1992
  • NR 1.3/13
  • NR 2.2/L3
  • NR 2.2/L3/1990
  • NR 2/2.1/1989
  • NR 3.1/1985
  • NR 12.2/F34/1985
  • NR 12.2/G87/1983
  • NR 12/20.1/1988
  • NR 12/20.2/P27/1991
  • NR 12/20.13/1979
If you are having difficulty locating a government publication in the collection, please see a Government Publications staff member.
Comments, additions and corrections are appreciated.
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