Classification
P - Language and Literature
514,016
M - Music
12,657
F - General American History
12,468
B - Philosophy, Psychology, Religion
9,554
Q - Science
8,475
A - General Works
6,654
H - Social Science
6,636
D - World History
4,768
C - Historical Sciences
4,686
K - Law
4,423
E - United States History
2,978
R - Medicine
2,121
T - Technology
2,080
N - Fine Arts
1,702
S - Agriculture
1,407
J - Political Science
1,269
G - Geography, Anthropology, Recreation
875
L - Education
838
Z - Library Science
343
U - Military Science
141
V - Naval Science
26