Número de Clasificación
Q - Science
123,689
T - Technology
106,502
H - Social Science
74,052
P - Language and Literature
44,763
D - World History
38,428
B - Philosophy, Psychology, Religion
28,156
R - Medicine
26,066
N - Fine Arts
25,726
K - Law
18,278
J - Political Science
14,634
G - Geography, Anthropology, Recreation
14,488
M - Music
11,619
L - Education
11,523
S - Agriculture
10,932
F - General American History
7,975
Z - Library Science
7,722
C - Historical Sciences
5,271
E - United States History
3,822
A - General Works
3,018
U - Military Science
2,716
V - Naval Science
1,316