Classification
550 - Earth sciences
606
551 - Geology, hydrology & meteorology
349
526 - Mathematical geography
183
520 - Astronomy & allied sciences
170
530 - Physics
86
621 - Applied physics
81
910 - Geography & travel
70
523 - Specific celestial bodies & phenomena
65
333 - Economics of land & energy
61
624 - Civil engineering
59
363 - Other social problems & services
34
629 - Other branches of engineering
30
620 - Engineering & allied operations
27
549 - Mineralogy
23
500 - Natural sciences & mathematics
21
900 - History & geography
20
531 - Classical mechanics; solid mechanics
18
534 - Sound & related vibrations
16
540 - Chemistry & allied sciences
14
700 - The arts; fine & decorative arts
14
000 - Computer science, information & general works
12
519 - Probabilities & applied mathematics
11
577 - Ecology
11
600 - Technology
11
515 - Analysis
10
518 - Numerical analysis
8
539 - Modern physics
8
541 - Physical chemistry
8
537 - Electricity & electronics
7
140 - Specific philosophical schools
6
631 - Techniques, equipment & materials
6
003 - Systems
5
304 - Factors affecting social behavior
5
380 - Commerce, communications & transportation
5
576 - Genetics & evolution
5
578 - Natural history of organisms
5
628 - Sanitary & municipal engineering
5
630 - Agriculture & related technologies
5
340 - Law
4
510 - Mathematics
4
535 - Light & infrared & ultraviolet phenomena
4
553 - Economic geology
4
610 - Medicine & health
4
006 - Special computer methods
3
300 - Social sciences
3
330 - Economics
3
414 - Phonology & phonetics
3
532 - Fluid mechanics; liquid mechanics
3
536 - Heat
3
580 - Plants (Botany)
3
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