Classification
551 - Geology, hydrology & meteorology
766
624 - Civil engineering
207
550 - Earth sciences
132
577 - Ecology
105
549 - Mineralogy
92
333 - Economics of land & energy
76
363 - Other social problems & services
58
910 - Geography & travel
56
620 - Engineering & allied operations
50
300 - Social sciences
49
001 - Knowledge
45
541 - Physical chemistry
34
621 - Applied physics
33
519 - Probabilities & applied mathematics
29
526 - Mathematical geography
26
531 - Classical mechanics; solid mechanics
25
553 - Economic geology
25
006 - Special computer methods
20
520 - Astronomy & allied sciences
20
570 - Life sciences; biology
19
560 - Paleontology; paleozoology
17
580 - Plants (Botany)
17
631 - Techniques, equipment & materials
17
530 - Physics
16
628 - Sanitary & municipal engineering
16
500 - Natural sciences & mathematics
15
523 - Specific celestial bodies & phenomena
14
590 - Animals (Zoology)
13
571 - Physiology & related subjects
11
630 - Agriculture & related technologies
11
690 - Buildings
11
576 - Genetics & evolution
10
501 - Philosophy & theory
9
543 - Analytical chemistry
9
050 - General serial publications
8
616 - Diseases
8
660 - Chemical engineering
8
301 - Sociology & anthropology
7
546 - Inorganic chemistry
7
900 - History & geography
7
005 - Computer programming, programs & data
6
515 - Analysis
6
572 - Biochemistry
6
579 - Microorganisms, fungi & algae
6
536 - Heat
5
538 - Magnetism
5
540 - Chemistry & allied sciences
5
548 - Crystallography
5
930 - History of ancient world to ca. 499
5
003 - Systems
4
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