Classification
005 - Computer programming, programs & data
490
004 - Data processing & computer science
286
006 - Special computer methods
272
620 - Engineering & allied operations
216
621 - Applied physics
194
330 - Economics
157
658 - General management
125
003 - Systems
103
519 - Probabilities & applied mathematics
99
500 - Natural sciences & mathematics
85
530 - Physics
68
616 - Diseases
67
551 - Geology, hydrology & meteorology
55
300 - Social sciences
52
610 - Medicine & health
52
331 - Labor economics
51
518 - Numerical analysis
51
629 - Other branches of engineering
50
338 - Production
38
001 - Knowledge
37
577 - Ecology
37
571 - Physiology & related subjects
32
670 - Manufacturing
32
332 - Financial economics
31
520 - Astronomy & allied sciences
30
384 - Communications; telecommunication
28
541 - Physical chemistry
27
572 - Biochemistry
27
333 - Economics of land & energy
24
510 - Mathematics
23
612 - Human physiology
22
745 - Decorative arts
22
025 - Library operations
21
515 - Analysis
21
550 - Earth sciences
21
302 - Social interaction
20
570 - Life sciences; biology
20
624 - Civil engineering
20
304 - Factors affecting social behavior
19
539 - Modern physics
19
000 - Computer science, information & general works
18
523 - Specific celestial bodies & phenomena
18
531 - Classical mechanics; solid mechanics
17
511 - General principles of mathematics
14
301 - Sociology & anthropology
12
363 - Other social problems & services
12
512 - Algebra
12
374 - Adult education
11
543 - Analytical chemistry
11
576 - Genetics & evolution
11
more ...