Classification
D - World History
34
H - Social Science
27
E - United States History
13
P - Language and Literature
9
L - Education
6
M - Music
6
B - Philosophy, Psychology, Religion
4
Z - Library Science
3
R - Medicine
2
G - Geography, Anthropology, Recreation
1
J - Political Science
1
K - Law
1
S - Agriculture
1
T - Technology
1