Answered By: Christine Stark
Last Updated: Aug 18, 2015     Views: 50

The University of Calgary Libraries, other than Doucette Library, use the Library of Congress Classification System (LC). Doucette Library uses the Dewey Decimal System. For libraries which use LC, materials are assigned and organized by unique alphanumeric call numbers. These call numbers are determined by the material’s disciplinary focus in addition to the material’s more specific characteristics (such as author or title), and operate in a progressive sequence. This can best be explained by breaking the following call number up into five parts using the following example.

PA 4025 A5M74 1995 v.2

PA: These leading letters refer to the book’s disciplinary focus.

These leading letters are organized ALPHABETICALLY. This means the call numbers will follow in the order:



4025: This first set of numbers further describes the book’s topic.

These numbers are WHOLE NUMBERS and are organized within the confines of the aforementioned alphabetical order. That is:

PA 1PA 2 PA 100PA 4025

This second part of the call number may also contain a decimal component which will operate like this:

PA 1PA 1.12 PA 1.7


A5M74: This alphanumeric section is the "cutter number" which further distinguishes the book by encoding the author, title, subject, or geographic area, etc.

Like before, the letters are organized ALPHABETICALLY. However, in the cutter number, the numbers are DECIMALS. Therefore, the call number PA 4025 A5M74 is read as PA 4025 A .5 M .74. This means:

PA 4025 A25M6PA 4025 A4M56PA 4025 A5M74… 


1995: This is the year the book was published.

The years are organized in numerical order.

PA 4025 A5M74 1987PA 4025 A5M74 1995 4025 A5M74 2000.

Not all books will have a year listed in the call number.  These call numbers without years will come before later editions of the book that list the year.


v.2: This part of the call number provides additional information about the book.

In this example, it supplies the specific volume number of a book from a multi-volume work. Volumes are organized in ascending order: v.1v.2

Some books will have a copy number instead of, or in addition to, the volume number. Copy numbers are denoted by c. #.  This indicates that the Library has more than one copy of the same book.  So, a book with c.3 at the end of the call number indicates it is the third copy of that same book in the Library's possession.