Topogràfic
L - Education
395
H - Social Science
18
F - General American History
10
Q - Science
10
K - Law
8
P - Language and Literature
6
G - Geography, Anthropology, Recreation
5
N - Fine Arts
4
T - Technology
3
B - Filosofia, Psicologia, Religió
2
R - Medicine
2
A - Treballs generalss
1
Z - Library Science
1