Classification
520 - Astronomy & allied sciences
1,040
523 - Specific celestial bodies & phenomena
698
530 - Physics
361
500 - Natural sciences & mathematics
199
539 - Modern physics
192
333 - Economics of land & energy
30
550 - Earth sciences
30
621 - Applied physics
30
519 - Probabilities & applied mathematics
25
576 - Genetics & evolution
24
620 - Engineering & allied operations
23
551 - Geology, hydrology & meteorology
21
700 - The arts; fine & decorative arts
20
004 - Data processing & computer science
19
300 - Social sciences
18
515 - Analysis
17
518 - Numerical analysis
17
541 - Physical chemistry
16
001 - Knowledge
15
000 - Computer science, information & general works
14
531 - Classical mechanics; solid mechanics
14
006 - Special computer methods
13
532 - Fluid mechanics; liquid mechanics
13
629 - Other branches of engineering
13
537 - Electricity & electronics
12
005 - Computer programming, programs & data
11
510 - Mathematics
11
570 - Life sciences; biology
10
370 - Education
9
306 - Culture & institutions
8
003 - Systems
7
526 - Mathematical geography
7
535 - Light & infrared & ultraviolet phenomena
7
536 - Heat
7
501 - Philosophy & theory
6
540 - Chemistry & allied sciences
5
572 - Biochemistry
5
050 - General serial publications
4
509 - Historical, geographic & persons treatment
4
533 - Gas mechanics
4
534 - Sound & related vibrations
4
538 - Magnetism
4
658 - General management
4
910 - Geography & travel
4
301 - Sociology & anthropology
3
330 - Economics
3
331 - Labor economics
3
338 - Production
3
516 - Geometry
3
546 - Inorganic chemistry
3
more ...