Classification
500 - Natural sciences & mathematics
004 - Data processing & computer science
669
331 - Labor economics
209
658 - General management
188
330 - Economics
112
620 - Engineering & allied operations
108
384 - Communications; telecommunication
102
000 - Computer science, information & general works
84
700 - The arts; fine & decorative arts
73
745 - Decorative arts
73
005 - Computer programming, programs & data
46
333 - Economics of land & energy
40
380 - Commerce, communications & transportation
37
300 - Social sciences
35
510 - Mathematics
34
600 - Technology
34
530 - Physics
30
338 - Production
29
003 - Systems
28
374 - Adult education
28
900 - History & geography
28
100 - Philosophy & psychology
27
302 - Social interaction
25
576 - Genetics & evolution
25
340 - Law
23
670 - Manufacturing
22
363 - Other social problems & services
20
006 - Special computer methods
19
140 - Specific philosophical schools
16
520 - Astronomy & allied sciences
15
320 - Political science
14
370 - Education
14
610 - Medicine & health
13
381 - Commerce
12
621 - Applied physics
12
519 - Probabilities & applied mathematics
9
720 - Architecture
9
400 - Language
6
539 - Modern physics
6
153 - Mental processes & intelligence
5
410 - Linguistics
5
001 - Knowledge
4
120 - Epistemology, causation & humankind
4
303 - Social processes
4
305 - Social groups
4
371 - Schools & their activities; special education
4
511 - General principles of mathematics
4
540 - Chemistry & allied sciences
4
629 - Other branches of engineering
4
808 - Rhetoric & collections of literature
4
more ...