Classification
H - Social Science
12
Q - Science
9
D - World History
7
A - General Works
6
K - Law
6
S - Agriculture
6
J - Political Science
5
B - Philosophy, Psychology, Religion
4
R - Medicine
4
E - United States History
3
N - Fine Arts
3
P - Language and Literature
3
T - Technology
3
F - General American History
2
C - Historical Sciences
1
Z - Library Science
1