Topogràfic
H - Social Science
200
J - Political Science
139
F - General American History
88
Q - Science
73
K - Law
65
L - Education
40
P - Language and Literature
36
G - Geography, Anthropology, Recreation
18
R - Medicine
16
B - Filosofia, Psicologia, Religió
8
T - Technology
6
E - United States History
4
M - Music
3
N - Fine Arts
3
S - Agriculture
3
C - Historical Sciences
2
A - Treballs generalss
1
D - World History
1
U - Military Science
1
Z - Library Science
1