Classification
550 - Earth sciences
910 - Geography & travel
86
551 - Geology, hydrology & meteorology
4
000 - Computer science, information & general works
3
363 - Other social problems & services
3
320 - Political science
2
330 - Economics
2
333 - Economics of land & energy
2
526 - Mathematical geography
2
610 - Medicine & health
2
304 - Factors affecting social behavior
1
370 - Education
1
630 - Agriculture & related technologies
1
658 - General management
1
700 - The arts; fine & decorative arts
1