Classification
629 - Other branches of engineering
17
520 - Astronomy & allied sciences
6
500 - Natural sciences & mathematics
3
523 - Specific celestial bodies & phenomena
2
551 - Geology, hydrology & meteorology
1
571 - Physiology & related subjects
1
600 - Technology
1
617 - Surgery & related medical specialties
1
620 - Engineering & allied operations
1
660 - Chemical engineering
1