Classification
539 - Modern physics
210
530 - Physics
154
523 - Specific celestial bodies & phenomena
41
621 - Applied physics
41
620 - Engineering & allied operations
20
541 - Physical chemistry
19
500 - Natural sciences & mathematics
16
520 - Astronomy & allied sciences
16
537 - Electricity & electronics
10
333 - Economics of land & energy
8
531 - Classical mechanics; solid mechanics
7
535 - Light & infrared & ultraviolet phenomena
6
700 - The arts; fine & decorative arts
5
536 - Heat
3
550 - Earth sciences
3
571 - Physiology & related subjects
3
526 - Mathematical geography
2
532 - Fluid mechanics; liquid mechanics
2
533 - Gas mechanics
2
534 - Sound & related vibrations
2
538 - Magnetism
2
628 - Sanitary & municipal engineering
2
660 - Chemical engineering
2
667 - Cleaning, color & coating technologies
2
000 - Computer science, information & general works
1
003 - Systems
1
004 - Data processing & computer science
1
006 - Special computer methods
1
340 - Law
1
380 - Commerce, communications & transportation
1
516 - Geometry
1
519 - Probabilities & applied mathematics
1
540 - Chemistry & allied sciences
1
543 - Analytical chemistry
1
546 - Inorganic chemistry
1
547 - Organic chemistry
1
548 - Crystallography
1
549 - Mineralogy
1
570 - Life sciences; biology
1
600 - Technology
1
610 - Medicine & health
1
612 - Human physiology
1
629 - Other branches of engineering
1
636 - Animal husbandry
1
900 - History & geography
1