Classification
330 - Economics
763
621 - Applied physics
21
620 - Engineering & allied operations
6
333 - Economics of land & energy
4
338 - Production
4
550 - Earth sciences
3
577 - Ecology
3
530 - Physics
2
629 - Other branches of engineering
2
327 - International relations
1
523 - Specific celestial bodies & phenomena
1
531 - Classical mechanics; solid mechanics
1
536 - Heat
1
553 - Economic geology
1
624 - Civil engineering
1
628 - Sanitary & municipal engineering
1
660 - Chemical engineering
1
670 - Manufacturing
1