Topogràfic
H - Social Science
65
K - Law
60
F - General American History
31
P - Language and Literature
18
J - Political Science
17
L - Education
9
G - Geography, Anthropology, Recreation
7
N - Fine Arts
7
Q - Science
3
U - Military Science
3
A - Treballs generalss
2
R - Medicine
2
T - Technology
2
B - Filosofia, Psicologia, Religió
1
C - Historical Sciences
1
M - Music
1