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Library Help: Call Numbers

Dewey Decimal Classification System

What Does a Dewey Decimal Call Number Look Like?

What does a Dewey Decimal call number look like?

For example, to find the book As Sociology Meets History, by C. Tilly (call number 907.2 T579a, 1981):

907.2 T579a, 1981
  1. Locate the first three digits.
  2. Locate any digits following the decimal point. Remember that it is a decimal system, so 907.2 comes after 907.18.
  3. When you have located the number in full, look for the letter, then the next set of numbers.
  4. Check that the last letter and number are correct, to make sure you have the right book and edition.

Locations and call numbers look like this:

In the Catalog: On the Item Label:
Reference Area 031 E56, 1994 R
Main Stacks 712.5 R895g 712.5
Upper Level
(Second Floor of the Library)
808.8 B 368t 808.8
Leisure Reading
(Front of the Library)
Shelved alphabetically by author's last name McNaughton

A Sample screen includes the following:

Author Pinker, Steven, 1954- author.
Title The sense of style : the thinking person's guide to writing in the 21st century / Steven Pinker.
Pub info New York : Penguin Books, 2015. ©2014
Descript viii, 359 pages : illustrations ; 21 cm
Note Includes glossary (pages 309-318).
Subject Rhetoric.
  UPPER LEVEL  808.02 P655s, 2015   AVAILABLE



Library of Congress Classification System

What is a Call Number?

What is a call number?

  • The shelf location, i.e., the "unique address" of the book.
    This shows the exact position of the item within the library, and the subject area.
  • The subject classification (for example: 800 Literature, 900 History & Geography, etc.).
    This attempts to place items on the same subject together.
    The classification scheme used in our Library is the Dewey Decimal Classification.
  • The link between the catalog and the shelves.
    All items listed in the catalog have a call number which is used, along with location (the "neighborhood"), to find the item on the shelves.

What if Book is Not on the Shelf?

What do I do if it is not on the shelf?

  • Check the reshelving areas. Also check around the photocopiers.
  • Look around the study tables and carrels where another user may have left it.
  • Double check the catalog - did you write the call number down correctly? Is it checked out? In Reference? On Reserve?
  • If you have looked for it several times on different days, ask the Librarian at the Information Desk for help or to start a "Missing Item" search for you.
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