Classification
539 - Modern physics
105
530 - Physics
41
523 - Specific celestial bodies & phenomena
16
333 - Economics of land & energy
4
621 - Applied physics
4
520 - Astronomy & allied sciences
3
500 - Natural sciences & mathematics
2
700 - The arts; fine & decorative arts
2
338 - Production
1
363 - Other social problems & services
1
501 - Philosophy & theory
1
531 - Classical mechanics; solid mechanics
1
535 - Light & infrared & ultraviolet phenomena
1
537 - Electricity & electronics
1
541 - Physical chemistry
1
610 - Medicine & health
1