Classification
Q - Science
189
D - World History
44
F - General American History
27
T - Technology
18
C - Historical Sciences
17
E - United States History
13
P - Language and Literature
6
R - Medicine
6
B - Philosophy, Psychology, Religion
5
G - Geography, Anthropology, Recreation
5
Z - Library Science
5
M - Music
4
S - Agriculture
3
A - General Works
2
H - Social Science
2