Classification
320 - Political science
330 - Economics
340 - Law
7,392
900 - History & geography
6,842
300 - Social sciences
6,081
630 - Agriculture & related technologies
2,376
700 - The arts; fine & decorative arts
1,586
576 - Genetics & evolution
1,364
333 - Economics of land & energy
809
370 - Education
758
200 - Religion
587
610 - Medicine & health
466
363 - Other social problems & services
367
170 - Ethics
343
100 - Philosophy & psychology
333
600 - Technology
327
800 - Literature & rhetoric
264
380 - Commerce, communications & transportation
203
304 - Factors affecting social behavior
194
500 - Natural sciences & mathematics
174
140 - Specific philosophical schools
173
000 - Computer science, information & general works
162
160 - Logic
118
400 - Language
97
551 - Geology, hydrology & meteorology
86
720 - Architecture
86
361 - Social problems & social welfare in general
81
336 - Public finance
76
620 - Engineering & allied operations
70
780 - Music
64
658 - General management
50
350 - Public administration & military science
45
301 - Sociology & anthropology
44
581 - Specific topics in natural history
44
530 - Physics
21
650 - Management & auxiliary services
21
657 - Accounting
21
580 - Plants (Botany)
20
360 - Social problems & services; associations
19
297 - Islam, Babism & Bahai Faith
17
550 - Earth sciences
16
920 - Biography, genealogy & insignia
16
410 - Linguistics
14
332 - Financial economics
11
364 - Criminology
8
520 - Astronomy & allied sciences
7
540 - Chemistry & allied sciences
7
414 - Phonology & phonetics
6
770 - Photography, photographs & computer art
6
296 - Judaism
5
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