Classification
H - Social Science
18
D - World History
8
N - Fine Arts
5
T - Technology
4
G - Geography, Anthropology, Recreation
3
S - Agriculture
3
Z - Library Science
3
J - Political Science
2
P - Language and Literature
2
R - Medicine
2
A - General Works
1
B - Philosophy, Psychology, Religion
1
C - Historical Sciences
1
F - General American History
1
Q - Science
1