How to Read Call Numbers
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Library of Congress call numbers should be read one line at a time as follows:
Example of a complete call number:
1. First, look at Line 1:
Books are arranged in alphabetical order , by the letters on the first line of the call number.
Example: first come all the D call numbers, then all the DA call numbers, then DB , etc.
2. Next, look at Line 2:
Within the DA call numbers, books are arranged in number order .
The numbers are arranged in numerical order, from low to high.
3. Then look at Line 3:
Line 3 of the call number has a letter and a number. The letters are in alphabetical order.
Then read the numbers -but BEWARE !
The numbers are not WHOLE numbers, they are DECIMAL numbers!
Example: A55 is read as A .55 - this is why A55 comes before A6 ( A .55, A .6, A .65, etc. )
Last modified: July 6, 2011