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First Year Students: Library of Congress Call Numbers

An introduction to the library's resources for first year students.

Library of Congress Call Numbers

Zahnow library uses Library of Congress Call numbers, an alphanumeric system which groups books by subject.  

This string of letters and numbers is used to organize books within the library.  The call number tells you where the book is located on the shelf.  

Call numbers are located on the books' spine and can be found within the library's online catalog (Classic Catalog and We Search).


Screenshot - Library of Congress Call Number

 

Call numbers on spine of books

Reading Call Numbers

Tips for Finding Books on the Shelf

Call number 'LB 2395 .C65 1991' on the spine of a book and in the online catalog

Read call numbers line by line.

LB
Read the first line in alphabetical order:
A, B, BF, C, D... L, LA, LB, LC, M, ML...

2395
Read the second line as a whole number:
1, 2, 3, 45, 100, 101, 1000, 2000, 2430...

.C65
The third line is a combination of a letter and numbers. Read the letter alphabetically. Read the number as a decimal, eg:
.C65 = .65 .C724 = .724

Some call numbers have more than one combination letter-number line.

1991
The last line is the year the book was published. Read in chronological order:
1985, 1991, 1992...

Here is a shelf of books with the call number order explained.

Ten Library of Congress call numbers in order on a shelf. On the first line, 'LA' before 'LB'.  On the second line, '2327' before '2328'. On the combination letter number line 'B' before 'C'. For the numbers after the letter on the combination line, '.55' before '.554' and '.554' before '.63'.  For the last line, '1987' before '1991'.

Credit: The Online Learning Center: http://www.usg.edu/galileo/skills/unit03/libraries03_04.phtml