Classification
330 - Economics
99
300 - Social sciences
72
500 - Natural sciences & mathematics
71
616 - Diseases
58
620 - Engineering & allied operations
58
577 - Ecology
56
006 - Special computer methods
53
320 - Political science
52
005 - Computer programming, programs & data
50
004 - Data processing & computer science
48
621 - Applied physics
47
510 - Mathematics
43
551 - Geology, hydrology & meteorology
43
001 - Knowledge
42
333 - Economics of land & energy
37
501 - Philosophy & theory
37
900 - History & geography
35
617 - Surgery & related medical specialties
32
610 - Medicine & health
31
520 - Astronomy & allied sciences
30
580 - Plants (Botany)
30
550 - Earth sciences
27
664 - Food technology
27
658 - General management
26
340 - Law
24
519 - Probabilities & applied mathematics
24
641 - Food & drink
24
910 - Geography & travel
24
301 - Sociology & anthropology
23
530 - Physics
23
304 - Factors affecting social behavior
22
363 - Other social problems & services
22
306 - Culture & institutions
20
338 - Production
20
331 - Labor economics
17
509 - Historical, geographic & persons treatment
17
576 - Genetics & evolution
17
570 - Life sciences; biology
16
003 - Systems
15
571 - Physiology & related subjects
15
612 - Human physiology
15
302 - Social interaction
14
624 - Civil engineering
14
650 - Management & auxiliary services
14
327 - International relations
13
572 - Biochemistry
13
600 - Technology
13
511 - General principles of mathematics
12
515 - Analysis
11
150 - Psychology
10
more ...