Classification
540 - Chemistry & allied sciences
595
570 - Life sciences; biology
206
500 - Natural sciences & mathematics
107
620 - Engineering & allied operations
100
600 - Technology
63
550 - Earth sciences
54
510 - Mathematics
48
541 - Physical chemistry
47
519 - Probabilities & applied mathematics
44
530 - Physics
37
621 - Applied physics
29
610 - Medicine & health
25
660 - Chemical engineering
20
300 - Social sciences
18
551 - Geology, hydrology & meteorology
18
150 - Psychology
17
547 - Organic chemistry
17
306 - Culture & institutions
11
577 - Ecology
10
612 - Human physiology
10
006 - Special computer methods
9
615 - Pharmacology & therapeutics
9
005 - Computer programming, programs & data
8
502 - Miscellany
8
572 - Biochemistry
8
616 - Diseases
8
539 - Modern physics
7
001 - Knowledge
6
155 - Differential & developmental psychology
6
363 - Other social problems & services
6
537 - Electricity & electronics
6
543 - Analytical chemistry
6
599 - Mammals
6
629 - Other branches of engineering
6
658 - General management
6
330 - Economics
5
332 - Financial economics
5
548 - Crystallography
5
003 - Systems
4
302 - Social interaction
4
343 - Military, tax, trade & industrial law
4
511 - General principles of mathematics
4
546 - Inorganic chemistry
4
571 - Physiology & related subjects
4
617 - Surgery & related medical specialties
4
153 - Mental processes & intelligence
3
301 - Sociology & anthropology
3
401 - Philosophy & theory
3
516 - Geometry
3
535 - Light & infrared & ultraviolet phenomena
3
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