Classification
500 - Natural sciences & mathematics
330 - Economics
248
520 - Astronomy & allied sciences
171
320 - Political science
168
620 - Engineering & allied operations
113
300 - Social sciences
105
658 - General management
104
005 - Computer programming, programs & data
86
302 - Social interaction
60
331 - Labor economics
54
670 - Manufacturing
54
370 - Education
52
900 - History & geography
51
000 - Computer science, information & general works
46
004 - Data processing & computer science
41
700 - The arts; fine & decorative arts
40
333 - Economics of land & energy
37
600 - Technology
34
006 - Special computer methods
31
338 - Production
27
363 - Other social problems & services
23
384 - Communications; telecommunication
23
510 - Mathematics
21
530 - Physics
19
745 - Decorative arts
19
100 - Philosophy & psychology
18
610 - Medicine & health
16
381 - Commerce
14
800 - Literature & rhetoric
14
380 - Commerce, communications & transportation
13
400 - Language
13
158 - Applied psychology
12
303 - Social processes
11
621 - Applied physics
11
340 - Law
10
650 - Management & auxiliary services
10
140 - Specific philosophical schools
9
332 - Financial economics
8
410 - Linguistics
8
519 - Probabilities & applied mathematics
7
001 - Knowledge
6
304 - Factors affecting social behavior
6
630 - Agriculture & related technologies
6
780 - Music
6
153 - Mental processes & intelligence
5
540 - Chemistry & allied sciences
5
551 - Geology, hydrology & meteorology
5
581 - Specific topics in natural history
5
629 - Other branches of engineering
5
660 - Chemical engineering
5
more ...