Library Call Numbers / Classification Systems
The majority of the Library's collections are shelved by the Library of Congress Classification System. Another substantial collection of materials, on the Lower Level of the John Crerar Library, is shelved by the Dewey Decimal Classification System. In addition, you may encounter several other classification systems, including Benyon K, Harvard Yenching, and Superintendent of Documents (SuDocs).
The Library of Congress Classification System
The University of Chicago, like most universities and research libraries in the United States, use the Library of Congress Classification System (LC).
The Library of Congress call numbers use a combination of letters and numbers to represent subject areas, allowing you to browse the shelves for similar books. See an overview of the Library of Congress Classification System. Most major universities and research libraries use the Library of Congress classification system.
To read a Library of Congress call number:
| PS3551 | The numbers following the letter(s)
are read as a whole number (three thousand five hundred and fifty-one).
PS3551 would come before PS3650. |
| .5 | If there are additional numbers immediately
after the whole number, you should treat them as a decimal. PS3551.5 would come between PS3551 and PS3552. |
| .N257 U53 |
For the next part of the call number, go to
the letter(s) and then treat the number(s) as a decimal. .N257 U53 would come between .N257 U450 and .N257 U6. |
| 1999 | The final number, if included, is the year
of publication. This book was published in 1999. |
Be sure to check the location listed in the Library Catalog before locating
your call number on the Library's
maps and call number guides. Call number ranges can repeat in different
locations throughout the Library. For more information, Ask
a Librarian for assistance.
Dewey Decimal Classification System
A portion of the John Crerar Library collections on the Lower Level is arranged using the Dewey Decimal Classification System. The Dewey Decimal System uses decimals to represent specific subject areas. View an overview of the Dewey Decimal System. While the Dewey Decimal System is commonly used in public and school libraries, some academic institutions (such as Northwestern and University of Illinois) use this as their primary classification system.
To read a Dewey Decimal call number:
| 630.51 | The number in front of the decimal is read
as a whole number (six hundred and thirty), then treat the rest as a decimal. 630.51 would come between 630.5 and 630.52. |
| P884 | For the final number, go to the letter first
and then read the rest as a whole number. P884 would come between P883 and P885. |
For information about the Dewey Collection, ask a Science
Librarian for assistance.
Other Classification Systems
Benyon K
The Library of Congress did not develop a classification scheme for legal materials until the late 1960's. In the late 1940's, Elizabeth Benyon, the Head of Technical Services at the University of Chicago Law Library, created a local classification system to organize the Law Library's collection. This system used the letter K because it was known at the time that the Library of Congress had already reserved this letter for legal materials, and it was hoped that the Library of Congress would adopt the Benyon system. When the Library of Congress classification scheme for legal materials was finally released, however, it was very different than what the University of Chicago's Benyon system.
In order to be consistent with other American law libraries, the D'Angelo Law Library adopted the Library of Congress law classification system ("LC K") for new items, but it continues to use the old Benyon K system for active titles that were classified prior to the advent of LC K, including primary law materials for the United States and Europe. In addition, Benyon K is still used to classify law journals, and most older items acquired before the creation of LC K have still not been re-classified and re-labeled into LC
In order to distinguish between the two systems, which both use the letter K, the D'Angelo Law Library adds the letters "XX" to the beginning of all LC K call numbers. These letters are an integral part of the call number and cannot be dropped off. From your perspective it should not matter whether a call number begins with "XXK," indicating that the item is classified under the LC K system, or "K," indicating that the item is classified under the Benyon K system. In either case you read the call number just as you would any other Library of Congress call number.
For more information, Ask a Law Librarian for assistance.
Harvard Yenching
Some of the materials in the Library's East Asian Collection are shelved by this system, which was created by the Harvard Yenching Library. Only materials added to the collection before 1987 use this system, and they are shelved on the B-Level of the Library. The rest of the East Asian materials are classified using the Library of Congress system.
Learn how to read
Harvard Yenching Call Numbers. For more information, contact the East
Asian area studies librarians for assistance.
Superintendent of Documents (SuDocs) Classification
System
Some government publications at Regenstein and D'Angelo are shelved by the Superintendent of Documents classification system. The rest will be shelved by LC Classification.
The University of Michigan Library has an excellent online tutorial to learn how to read SuDocs call numbers. For more information, Ask a Librarian for assistance.