Classification
539 - Modern physics
111
333 - Economics of land & energy
60
620 - Engineering & allied operations
56
621 - Applied physics
55
530 - Physics
34
520 - Astronomy & allied sciences
18
541 - Physical chemistry
18
006 - Special computer methods
16
500 - Natural sciences & mathematics
15
005 - Computer programming, programs & data
12
515 - Analysis
10
523 - Specific celestial bodies & phenomena
10
363 - Other social problems & services
8
600 - Technology
7
658 - General management
7
000 - Computer science, information & general works
6
540 - Chemistry & allied sciences
6
551 - Geology, hydrology & meteorology
6
001 - Knowledge
5
300 - Social sciences
5
330 - Economics
5
519 - Probabilities & applied mathematics
5
610 - Medicine & health
5
700 - The arts; fine & decorative arts
5
580 - Plants (Botany)
4
003 - Systems
3
510 - Mathematics
3
543 - Analytical chemistry
3
624 - Civil engineering
3
629 - Other branches of engineering
3
660 - Chemical engineering
3
004 - Data processing & computer science
2
320 - Political science
2
327 - International relations
2
518 - Numerical analysis
2
531 - Classical mechanics; solid mechanics
2
546 - Inorganic chemistry
2
571 - Physiology & related subjects
2
616 - Diseases
2
650 - Management & auxiliary services
2
670 - Manufacturing
2
040 - [Unassigned]
1
155 - Differential & developmental psychology
1
324 - The political process
1
331 - Labor economics
1
340 - Law
1
380 - Commerce, communications & transportation
1
414 - Phonology & phonetics
1
501 - Philosophy & theory
1
509 - Historical, geographic & persons treatment
1
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