Classification
300 - Social sciences
330 - Economics
658 - General management
227
302 - Social interaction
189
320 - Political science
160
500 - Natural sciences & mathematics
142
670 - Manufacturing
127
338 - Production
59
100 - Philosophy & psychology
48
331 - Labor economics
34
900 - History & geography
30
301 - Sociology & anthropology
28
650 - Management & auxiliary services
27
333 - Economics of land & energy
24
380 - Commerce, communications & transportation
24
170 - Ethics
23
384 - Communications; telecommunication
22
153 - Mental processes & intelligence
21
140 - Specific philosophical schools
17
332 - Financial economics
16
610 - Medicine & health
16
620 - Engineering & allied operations
16
158 - Applied psychology
15
370 - Education
14
600 - Technology
14
381 - Commerce
13
340 - Law
12
700 - The arts; fine & decorative arts
12
000 - Computer science, information & general works
11
363 - Other social problems & services
11
361 - Social problems & social welfare in general
9
200 - Religion
8
368 - Insurance
8
304 - Factors affecting social behavior
7
001 - Knowledge
6
576 - Genetics & evolution
6
400 - Language
5
410 - Linguistics
5
630 - Agriculture & related technologies
5
800 - Literature & rhetoric
5
004 - Data processing & computer science
4
720 - Architecture
4
780 - Music
4
150 - Psychology
3
337 - International economics
3
510 - Mathematics
3
657 - Accounting
3
770 - Photography, photographs & computer art
3
005 - Computer programming, programs & data
2
152 - Perception, movement, emotions & drives
2
more ...