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Library of Congress Classification System: A Brief Guide: How to Read LC Call Numbers

A brief explanation of the system used to find books in Dacus Library.

The First Set of Letters is Alphabetical

H HA HB HC
45 126 12 13
.B62 .F99 .I90 .C55
1990 .K9 1975 .C55

The Following Set of Numbers is in Numerical Order

B B B B
45 467 1200 1231
.H432 .K77 .P95 .C33
1980 1967 .A66 .I7
1990 1981

The Letters after the Decimal Point are Alphabetical

KF KF KF KF
456 456 456 456
.A43 .B99 .K99 .L7
.E45 1990 1987 1990
1993

The Numbers after the Decimal Point are in Decimal Order

L L L L
901 901 901 901
.C25 .C26 .C263 .C27
1977 1993 1988 1976

Note that .C263 is before .C27

Another Line of Letters and Numbers May Follow

These will be in alphabetical and decimal order.  The publication date may be included.

 

B B B B
1200 1200 1200 1200
.P95 .P95 .P95 .P95
.A65 .A651 .A66 .A87
1990 1974 1981 1966