Signum
P - Language and Literature
17 485
D - World History
11 943
B - Philosophy, Psychology, Religion
7 272
H - Social Science
4 061
N - Fine Arts
2 201
G - Geography, Anthropology, Recreation
1 686
C - Historical Sciences
1 491
K - Law
1 452
J - Political Science
925
Z - Library Science
908
M - Music
594
T - Technology
556
Q - Science
461
R - Medicine
454
U - Military Science
437
A - General Works
289
L - Education
255
S - Agriculture
249
F - General American History
207
V - Naval Science
137
E - United States History
108