Classification
620 - Engineering & allied operations
6,396
621 - Applied physics
3,580
005 - Computer programming, programs & data
1,668
004 - Data processing & computer science
1,128
629 - Other branches of engineering
1,106
624 - Civil engineering
715
519 - Probabilities & applied mathematics
654
670 - Manufacturing
628
658 - General management
520
006 - Special computer methods
517
003 - Systems
494
660 - Chemical engineering
342
530 - Physics
310
531 - Classical mechanics; solid mechanics
252
690 - Buildings
199
551 - Geology, hydrology & meteorology
165
515 - Analysis
161
610 - Medicine & health
147
363 - Other social problems & services
121
541 - Physical chemistry
91
518 - Numerical analysis
87
333 - Economics of land & energy
86
616 - Diseases
86
628 - Sanitary & municipal engineering
80
650 - Management & auxiliary services
75
539 - Modern physics
67
536 - Heat
66
338 - Production
62
534 - Sound & related vibrations
62
677 - Textiles
61
550 - Earth sciences
60
330 - Economics
59
537 - Electricity & electronics
58
520 - Astronomy & allied sciences
56
910 - Geography & travel
54
512 - Algebra
53
510 - Mathematics
48
511 - General principles of mathematics
48
540 - Chemistry & allied sciences
47
543 - Analytical chemistry
44
571 - Physiology & related subjects
43
500 - Natural sciences & mathematics
42
577 - Ecology
40
617 - Surgery & related medical specialties
37
570 - Life sciences; biology
28
516 - Geometry
25
535 - Light & infrared & ultraviolet phenomena
25
523 - Specific celestial bodies & phenomena
23
509 - Historical, geographic & persons treatment
22
720 - Architecture
22
more ...