Topogràfic
F - General American History
50
H - Social Science
47
P - Language and Literature
34
N - Fine Arts
26
J - Political Science
9
M - Music
8
L - Education
5
G - Geography, Anthropology, Recreation
3
K - Law
3
Z - Library Science
3
B - Filosofia, Psicologia, Religió
2
R - Medicine
2
E - United States History
1
T - Technology
1
U - Military Science
1