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P - Language and Literature
122
H - Social Science
51
J - Political Science
37
B - Filosofia, Psicologia, Religió
33
D - World History
32
F - General American History
26
N - Fine Arts
23
K - Law
21
L - Education
19
G - Geography, Anthropology, Recreation
16
T - Technology
12
Q - Science
11
R - Medicine
6
C - Historical Sciences
4
A - Treballs generalss
1
M - Music
1
Z - Library Science
1