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SuDocs Call Numbers

Government publications in the U.S. Documents Collection (both paper and microfiche) use a special call number system specifically created for federal documents, called the Superintendent of Documents (SuDocs) call number system.

The SuDocs call number system is based on the government agency which released the document. For example, a publication from the Department of Agriculture begins with an "A," such as A 1.114:92 and a publication from the Department of Education begins with the letters "ED," such as ED 1.209 Sp1.

Agencies or bureaus under departments have the letter or letters for that department (the "parent agency") and a number unique to the sub-agency or bureau. For example, "A 13" is the Forest Service and "A 93" is the Economic Research Service, both of which are agencies under the Department of Agriculture.

The next part of the call number identifies the series or type of publication. The remaining parts of the call number identify the individual publication.

The call numbers file alphabetically by letter and then in numerical order by the first group of numbers, then the next group, etc. All numbers are whole numbers. Unlike the Library of Congress call number system used in most of the rest of the library, THERE ARE NO DECIMALS.

Examples of Shelving Order

First the letter or letters at the beginning
Note: "Nothing comes before something."
A 1.1:985
AC 1.1/2:975
Then numerically by the number, stopping at the period. C 2.2:207
C 21.12/2:966
Then numerically by the whole number down to the next slash, period, or colon. C 55.13:826
C 55.13/2:26
If at any time after the first period you must choose between a number and a letter, letters go before numbers. Y 4.Ec7/a:92
Y 4.Ec7/2:86
Continue looking by the whole number or letter up to the next punctuation mark until the end of the call number. Y 4.F49:92-47
Y 4.F49:857

In the University of Delaware library catalogs: DELCAT or WorldCat Local, a government document with a SuDocs call number may have one of these locations:

  • U.S. Doc (Lower level of the Morris Library)
  • U.S. Doc Microfiche (Lower level of the Morris Library)
  • Library Annex (remote storage, use Library Annex Request Form)
This page is maintained by the Reference Department. Last modified: 07/15/11