Classification
530 - Physics
409
006 - Special computer methods
267
620 - Engineering & allied operations
255
621 - Applied physics
246
658 - General management
172
519 - Probabilities & applied mathematics
159
539 - Modern physics
140
005 - Computer programming, programs & data
127
616 - Diseases
121
541 - Physical chemistry
113
610 - Medicine & health
97
320 - Political science
91
003 - Systems
89
523 - Specific celestial bodies & phenomena
87
004 - Data processing & computer science
85
304 - Factors affecting social behavior
79
306 - Culture & institutions
79
327 - International relations
79
515 - Analysis
79
547 - Organic chemistry
77
629 - Other branches of engineering
72
571 - Physiology & related subjects
68
551 - Geology, hydrology & meteorology
61
370 - Education
60
338 - Production
58
330 - Economics
55
520 - Astronomy & allied sciences
52
612 - Human physiology
52
543 - Analytical chemistry
49
660 - Chemical engineering
47
333 - Economics of land & energy
46
302 - Social interaction
41
300 - Social sciences
39
332 - Financial economics
39
305 - Social groups
34
537 - Electricity & electronics
32
572 - Biochemistry
32
615 - Pharmacology & therapeutics
32
550 - Earth sciences
29
570 - Life sciences; biology
29
364 - Criminology
25
500 - Natural sciences & mathematics
25
910 - Geography & travel
25
535 - Light & infrared & ultraviolet phenomena
24
510 - Mathematics
23
363 - Other social problems & services
22
516 - Geometry
22
378 - Higher education
21
580 - Plants (Botany)
21
809 - History, description & criticism
21
more ...