Classification
333 - Economics of land & energy
581 - Specific topics in natural history
320 - Political science
3
330 - Economics
3
363 - Other social problems & services
3
551 - Geology, hydrology & meteorology
2
100 - Philosophy & psychology
1
300 - Social sciences
1
301 - Sociology & anthropology
1
600 - Technology
1
610 - Medicine & health
1
700 - The arts; fine & decorative arts
1
900 - History & geography
1