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Understanding Library of Congress Call Numbers
Library of Congress Call Numbers are arranged alphabetically and numerically. Read Call Numbers from left to right, and from top to bottom.
Letters in the first line of the Call Number are alphabetical:
| D53 .E476 1990 |
H155 .A5 1944 |
HA21 .A33 1982 |
HM13 .S47 1990 |
Numbers in the first line of the Call Number are in numerical order:
| D53 .E476 1990 |
D785 .L44 M67 1991 |
D1201 .B44 W64 1997 |
D1246 .R66 1986 |
Letters in the second line are alphabetical:
| D53 .E476 1990 |
D53 .G538 1989 |
D53 .R795 1995 |
D53 .T38 1989 |
Numbers in the second line of the Call Number are in decimal order. It is important to remember that there is an “invisible” decimal point between the letter and the number:
| D53 .E476 1990 |
D53 .E48 1971 |
D53 .E483 1976 |
D53 .E49 1996 |
There may be a third line of letters and numbers--these will also be in alphabetical and decimal number order.
The last line of a call number may be a year. This indicates the publication date.
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Created by
M. C. MacDonald 7/98