Classification
S - Agriculture
118
Q - Science
61
T - Technology
55
R - Medicine
22
M - Music
18
H - Social Science
17
G - Geography, Anthropology, Recreation
13
A - General Works
7
L - Education
7
Z - Library Science
4
F - General American History
2
N - Fine Arts
2
U - Military Science
2
C - Historical Sciences
1
D - World History
1
P - Language and Literature
1