The Library of Congress Classification is a system in which books are sorted by subject, into one of 21 main categories. These main categories contain subclasses (for example: Technology -> Bridge engineering).

Using the call number (code) on the spine of the book, library users can locate and find books from the collection. In a way, a call number can be seen as the “address” of a book.

How to read a call number

• The letters are in alphabetical order
• Within the main section of the classification (everything before the decimal point), the numbers are seen as whole numbers and are sorted numerically: BN2 - BN 12 - BN150.
• Cutter numbers (everything after the decimal point) are read as decimals. Keep in mind: the decimal point is not on the sticker of the spine of the book. You can recognise the cutter by looking at the first letter.

Examples

• D61 comes before D161 and after D11, but:
• D161.52 comes before D161.7
• D61 .B33 comes before D61 .B6 and after D61 .B254
• D61 .B3345 comes before D61 .B335 and after D61 .B33448

Take this quiz to practice the LCC system!​​​​​​​

The UBL distinguishes between open stacks and closed stacks. Open stacks refer to books located in the study areas and on the course reserve shelves. These books can only be perused within the library. Books in the study areas at the University Library and various other library locations are sorted according to the LCC system. Some of these books are loanable; others can be consulted at the library location in question. Consult the catalogue to find out if a book is loanable. Since the books are arranged by subject, it may be helpful to browse around your chosen book and see whether you can find something interesting for your research.

A major part of the library's collections is placed in closed stacks, which are not accessible for library visitors. These books need to be requested using the catalogue, if you want to borrow or consult them. Requested books are put in a locker for you to pick up. Books in closed stacks are not arranged according to the LCC. Read more about consulting books from the closed stacks on our page about borrowing.

Books on the first floor are categorized within the same LCC system. The alphabet starts in study area 1 (entrance 1) on the first floor, continues around the building, and ends in study area 8. Books on the first floor can be recognised by the I (Roman numeral one) preceding the call number.  The LCC alphabet starts anew in the Asian Library on the second floor.

Open this document to find your area of study in the UB.

Papyrology

A small additional alphabet has been inserted to mark papyrology books near the letter P. The call number for these books starts with the location prefix PAPY.

Special Collections

The books belonging to the Special Collections on the second floor are sorted, in alphabetical order, into two reference libraries: one for the visual collections (II-3) and one for the text collections (II-4).

Why do libraries use LCC call numbers?

Categorising books in this way makes it easy to browse within a particular subject area, as all books on the same topic are shelved near each other. It may be helpful to know the letter(s) representing your subject area to find a place to start browsing for relevant materials. Click here for an overview of the letters and titles of the main LCC classes.

Other terms to describe a call number within the UBL

Sometimes a call number is called differently, for example a shelf number. Other terms that may be used to refer to a call number within the UBL are LCC code (Dutch), shelf number, shelf code, shelfmark (especially used within the Special Collections) and signature.

Library of Congress Classification

Read more about LCC on the Library of Congress Classification website.