Classification
T - Technology
69
Q - Science
67
S - Agriculture
37
H - Social Science
29
R - Medicine
24
D - World History
13
L - Education
11
A - General Works
9
P - Language and Literature
9
G - Geography, Anthropology, Recreation
8
U - Military Science
5
K - Law
4
J - Political Science
3
Z - Library Science
3
B - Philosophy, Psychology, Religion
2
M - Music
2
N - Fine Arts
2
C - Historical Sciences
1