Classification
Q - Science
22
D - World History
13
P - Language and Literature
11
A - General Works
7
T - Technology
7
S - Agriculture
4
Z - Library Science
3
G - Geography, Anthropology, Recreation
2
H - Social Science
2
B - Philosophy, Psychology, Religion
1
C - Historical Sciences
1
J - Political Science
1
L - Education
1
N - Fine Arts
1