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How to Read Call Numbers

Step 2: Read the Call Number

After you have determined the location of the item, you need to understand how to read the call number

The call number is the address of the material - the exact location of where it lives on the shelf.

Where Do I Find the Call Number?

The call number can be found after the location in the Search It record.

“The history of Iran” catalog info with call number outlined: DS272 .D36 2012 located after "Available at Holland/Terrell Libraries Stacks"“History of manufacturers in the United States” catalog info with call number outlined: 338.4 C549h2 located after "Available at Holland/Terrell Libraries Deweys"“Soil survey, Crawford County, Wisconsin” catalog info with call number outlined: A 57.38:958/18 located after "Available at Owen Science and Engineering Library U.S. Government Documents"

The call number you see in Search It will then be located on the corresponding book, but will be listed horizontally. HOL stands for "Holland" - begin your reading of the call number AFTER this abbreviation (so in the photo below, start with BF).

Close up of call numbers of books arranged on a shelf all starting with, from top to bottom HOL. BF. 316 or 316.6 with more precise location beneath

Types of Call Numbers

There are 3 types of call numbers you may run into while using the WSU Libraries that you should know how to read:

1.  LC (Library of Congress) call numbers always start with one or two letters.


  • Holland and Terrell Libraries Stacks PN6710 P415 2011
  • Animal Health Library Stacks SF757 .B34 2000

Continue to Reading LC Call Numbers.

2. Dewey Decimal call numbers start with a number. These are usually older books.


  • Owen Science and Engineering Library Dewey  530 H295p3
  • Holland and Terrell Libraries Dewey  830.92 R457zf

Continue to Reading Dewey Call Numbers.

3.  SuDoc (government document) call numbers also start with a letter or two, but the location will tell you if it is a government document.


  • Owen Science and Engineering Library U.S.Gov-Doc  A 101.10/2:91-40
  • Holland and Terrell Libraries U.S.Gov-Docs  L 1.2:W 72/6

Continue to Reading SuDoc Call Numbers.

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