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:
H
45
.E37
1984 |
HA
155
.A5
1944 |
HB
21
.A33
1982 |
HC
13
.S47
1990 |
Numbers in the second line of the call number are in numerical order:
B
53
.D476
1990 |
B
785
.L44
M67
1991 |
B
1201
.B44
W64
1997 |
B
1246
.R66
1986 |
Letters in the third line are alphabetical:
KF
240
.B265
1981 |
KF
240
.C538
1989 |
KF
240
.S795
1995 |
KF
240
.T38
1989 |
Numbers in the third 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:
L
901
.C33 |
L
901
.C34
1971 |
L
901
.C343
1976 |
L
901
.C37
1996 |
There may be a fourth 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.