索引号
P - Language and Literature
72
H - Social Science
18
E - United States History
4
F - General American History
4
L - Education
4
B - Philosophy, Psychology, Religion
2
C - Historical Sciences
2
R - Medicine
2
T - Technology
2
D - World History
1
G - Geography, Anthropology, Recreation
1
K - Law
1
N - Fine Arts
1
S - Agriculture
1