Classification
330 - Economics
360 - Social problems & services; associations
320 - Political science
2
361 - Social problems & social welfare in general
2
610 - Medicine & health
2
300 - Social sciences
1
333 - Economics of land & energy
1
363 - Other social problems & services
1
370 - Education
1
551 - Geology, hydrology & meteorology
1
600 - Technology
1