Classification
330 - Economics
200
320 - Political science
129
900 - History & geography
89
333 - Economics of land & energy
77
610 - Medicine & health
45
304 - Factors affecting social behavior
36
370 - Education
36
700 - The arts; fine & decorative arts
36
820 - English & Old English literatures
35
363 - Other social problems & services
31
340 - Law
30
300 - Social sciences
21
000 - Computer science, information & general works
20
800 - Literature & rhetoric
18
600 - Technology
16
380 - Commerce, communications & transportation
14
140 - Specific philosophical schools
12
551 - Geology, hydrology & meteorology
11
630 - Agriculture & related technologies
11
580 - Plants (Botany)
10
200 - Religion
8
400 - Language
8
576 - Genetics & evolution
8
658 - General management
8
940 - History of Europe
8
301 - Sociology & anthropology
7
336 - Public finance
7
581 - Specific topics in natural history
6
620 - Engineering & allied operations
6
943 - Central Europe; Germany
6
297 - Islam, Babism & Bahai Faith
5
338 - Production
5
410 - Linguistics
5
361 - Social problems & social welfare in general
4
170 - Ethics
3
280 - Christian denominations & sects
3
305 - Social groups
3
332 - Financial economics
3
780 - Music
3
891 - East Indo-European & Celtic literatures
3
100 - Philosophy & psychology
2
270 - History of Christianity & Christian church
2
296 - Judaism
2
322 - Relation of state to organized groups
2
331 - Labor economics
2
347 - Civil procedure & courts
2
364 - Criminology
2
414 - Phonology & phonetics
2
500 - Natural sciences & mathematics
2
540 - Chemistry & allied sciences
2
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