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Find Physical Items on the Library Shelves: Home

Explanation of call numbers and tips on how to find physical books and other items by locating the call number on the online record and how to then find it on the shelves.

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What is a Call Number?

A Call Number...

  • ... represents what an item is about based on a classification system. The call numbers organize the items based on their contents, so items that have similar subject matter will be near each other. When you find a call number you use it to locate the item on the shelf, or browse that range for similar items.
  • ... is like an address that determines the book location (or other item) on the shelf. The call number is usually found on a label at the bottom of a book's spine.

Most academic libraries, like the DiMenna-Nyselius Library, use the Library of Congress Classification System when assigning call numbers to books and other items. This is also referred to as LC Classification. This organization system may be different from what you have encountered at public libraries, which use the Dewey Decimal System.

Intrigued? See a list of the letters and titles of the main classes of the Library of Congress Classification here. Click on any class to view an outline of its subclasses.

Finding Physical Library Items

1. Find the item Call Number

When you find the online record from the Library catalog for a print book or other physical item, there are three parts to note. They include the following:

  • Status
    If the status says 'Available' in green text it should be on the shelf. If the status says 'Unavailable' you want to make sure you are signed in so that you can put a request in for the book. When it becomes available you will receive a notification. If a book is unavailable, it could be because it is checked out, on hold for another patron, on order, etc. The status may also indicate 'Available Online', in which case you are able to click a link in the record to access an electronic version of the item.
  • Location
    The location tells you where in the library you can find an item. Ex: Stacks Upper Level, Stacks Lower Level, Reference Stacks Main Level, Curriculum Collection Upper Level, etc.
  • Call Number 
    The call number helps you locate the item on the shelf.  Ex: PS 153 .M56 I34 1997

Keep in mind that if a record says 'Reference Main Stacks' before the call number it can be accessed in the library but cannot leave the library. 

Image of Library catalog screenshot for The Great Gatsby with arrow pointing to the status, location, and call number line

Based on the example record above you would know to go to the Upper Level of the Library (top floor).


2.  Find the item on the shelf by going to the level of the library where the item is located (see example above for how the item record indicates the location).

The library's collection is shelved on all three levels of the building. It is organized on the following levels and can also be seen on our floor plan:

Lower Level:

  • Call Numbers A - C (shelved on moveable shelving)
  • Microfilm and Microfiche

Upper Level:

  • Call Numbers D - Z   (call numbers beginning with M and N are shelved on the counter height shelving along the windows)
  • Folio Books: These oversized books are located on shelving on either side of the staircase
  • Curriculum Collection: Books and kits for juvenile and middle school level. Many education majors utilize this collection.
  • DVDs: The DVD boxes may be locked or the discs will be available at the Library Services & Information Desk.

Main Level:

Reference Books: Non-circulating materials for quick reference that are meant to be used in the library. Select pages can be scanned or photocopied too.

  • New Books
  • Faculty Publications
  • Popular Reading: Best-selling fiction and non-fiction are shelved here. Book spines have genre stickers for browsing.
  • Young Adult books
  • Graphic Novels
  • New DVDs
  • Print newspapers and magazines
  • Course Reserves and Student Donated Textbook Collection : Shelved behind the Library Services & Information Desk.


3. Find the shelving row (referred to as a "stack" or "stacks") using the unique call number for the item.  There are signs on the ends of each row to indicate the call number range housed there. The first part of the call number is read alphabetically. Look at the box below for "How to Read a Call Number".


Picture of Stacks signage

How to Read a Call Number & Find the Item on the Shelf


Image of book spine labels that show Library of Congress classification call numbers


Call Number example as it would appear on the label spine of a book, DVD, or other item: 



The first part of the call number is arranged alphabetically and tells you the subject matter. Books of the same subject can be found near each other. To find it on the library shelf, look at the signs on the end of each shelf row and locate the P section, and then the PS section within it.

You read this as a whole number and they are ordered from low to high, so 151 before 152, etc. Sometimes, you will see it placed on the same line as the starting letters. The numbers may or may not have decimal points; but when they do, treat them numerically. For example, PS1234 comes before PS1234.23 and PS1233 comes before PS1234.

This is where it starts to get tricky. Begin alphabetically, just as before. Then, begin to read it as a decimal, arranged from smallest to largest decimal. In the example above, think of it as .56. Therefore, .M6 would come after .M56, because .56 is smaller than .6.

You read this line the same as the line above it, alphabetically and as a decimal.

This number indicates the year; generally the year of publication for that particular volume.

v.1 or c.2
Sometimes after the year you see v.1, v.2, etc or c.2, c.3, etc. 'V' is for volume and is included for items that are part of a multi volume set. 'C' is for copy, which indicates which library copy it is when multiple copies are owned.


Additionally, sometimes you may see 'Ref.', 'Folio', 'Faculty', or 'Curric.' before a call number. These are collection location indicators. See the box above on this guide above for more details for a list of collections on each level of the library.

Additional Information

If you can't find an item, or would like assistance from a library staff member, please ask someone to help you at the Library Services & Information Desk (main floor). 


Want to watch a brief video explaining how to read a call number in the Library of Congress Classification System? 

Want to learn more about the individual letter ranges in the Library of Congress Classification System?