Topogràfic
F - General American History
84
H - Social Science
25
P - Language and Literature
21
J - Political Science
5
A - Treballs generalss
4
E - United States History
4
G - Geography, Anthropology, Recreation
3
Q - Science
3
B - Filosofia, Psicologia, Religió
2
D - World History
2
L - Education
2
S - Agriculture
2
N - Fine Arts
1
R - Medicine
1
T - Technology
1