Classification
006 - Special computer methods
115
004 - Data processing & computer science
97
005 - Computer programming, programs & data
92
330 - Economics
56
610 - Medicine & health
54
370 - Education
52
300 - Social sciences
51
371 - Schools & their activities; special education
48
304 - Factors affecting social behavior
46
621 - Applied physics
46
616 - Diseases
40
333 - Economics of land & energy
38
500 - Natural sciences & mathematics
37
658 - General management
35
306 - Culture & institutions
32
519 - Probabilities & applied mathematics
32
620 - Engineering & allied operations
29
301 - Sociology & anthropology
25
320 - Political science
24
507 - Education, research & related topics
24
150 - Psychology
23
510 - Mathematics
21
577 - Ecology
18
001 - Knowledge
16
302 - Social interaction
15
338 - Production
15
613 - Personal health & safety
15
629 - Other branches of engineering
15
155 - Differential & developmental psychology
14
303 - Social processes
14
670 - Manufacturing
14
003 - Systems
13
614 - Incidence & prevention of disease
13
551 - Geology, hydrology & meteorology
12
615 - Pharmacology & therapeutics
12
025 - Library operations
11
363 - Other social problems & services
11
570 - Life sciences; biology
11
910 - Geography & travel
11
571 - Physiology & related subjects
10
617 - Surgery & related medical specialties
10
650 - Management & auxiliary services
10
331 - Labor economics
9
361 - Social problems & social welfare in general
9
501 - Philosophy & theory
9
530 - Physics
9
305 - Social groups
8
378 - Higher education
8
612 - Human physiology
8
630 - Agriculture & related technologies
8
more ...