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Main Campus: 215-751-8394 | NERC Learning Commons: 215-972-6270 | NWRC Library: 215-496-6019 | WERC Learning Commons: 267-299-5848
Dewey Decimal Classification System
The Community College of Philadelphia Library is based on the Dewey Decimal system. University of Illinois at Urbana-Champaign's Dewey Decimal System - How to Read a Call Number provides more information.
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):
- Locate the first three digits.
- Locate any digits following the decimal point. Remember that it is a decimal system, so 907.2 comes after 907.18.
- When you have located the number in full, look for the letter, then the next set of numbers.
- 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:
||031 E56, 1994
(Second Floor of the Library)
|808.8 B 368t
(Front of the Library)
|Shelved alphabetically by author's last name
A Sample screen includes the following:
||Pinker, Steven, 1954- author.
||The sense of style : the thinking person's guide to writing in the 21st century / Steven Pinker.
||New York : Penguin Books, 2015. ©2014
||viii, 359 pages : illustrations ; 21 cm
||Includes glossary (pages 309-318).
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.