Classification
363 - Other social problems & services
600 - Technology
620 - Engineering & allied operations
333 - Economics of land & energy
11
551 - Geology, hydrology & meteorology
7
630 - Agriculture & related technologies
7
900 - History & geography
6
140 - Specific philosophical schools
5
330 - Economics
5
540 - Chemistry & allied sciences
5
581 - Specific topics in natural history
5
300 - Social sciences
3
320 - Political science
3
580 - Plants (Botany)
3
590 - Animals (Zoology)
3
700 - The arts; fine & decorative arts
3
610 - Medicine & health
2
301 - Sociology & anthropology
1
500 - Natural sciences & mathematics
1
550 - Earth sciences
1
720 - Architecture
1