Classification
520 - Astronomy & allied sciences
245
523 - Specific celestial bodies & phenomena
161
500 - Natural sciences & mathematics
45
530 - Physics
24
519 - Probabilities & applied mathematics
5
539 - Modern physics
5
551 - Geology, hydrology & meteorology
2
001 - Knowledge
1
200 - Religion
1
300 - Social sciences
1
501 - Philosophy & theory
1
515 - Analysis
1
531 - Classical mechanics; solid mechanics
1
572 - Biochemistry
1
621 - Applied physics
1
629 - Other branches of engineering
1