Classification
100 - Philosophy & psychology
320 - Political science
330 - Economics
576 - Genetics & evolution
900 - History & geography
300 - Social sciences
4
140 - Specific philosophical schools
3
301 - Sociology & anthropology
3
333 - Economics of land & energy
2
340 - Law
2
363 - Other social problems & services
2
581 - Specific topics in natural history
2
600 - Technology
2
350 - Public administration & military science
1
370 - Education
1
610 - Medicine & health
1
620 - Engineering & allied operations
1
920 - Biography, genealogy & insignia
1