Classification
300 - Social sciences
320 - Political science
610 - Medicine & health
333 - Economics of land & energy
4
100 - Philosophy & psychology
3
900 - History & geography
3
301 - Sociology & anthropology
2
370 - Education
2
140 - Specific philosophical schools
1
330 - Economics
1
380 - Commerce, communications & transportation
1
581 - Specific topics in natural history
1
600 - Technology
1