Classification
100 - Philosophy & psychology
140 - Specific philosophical schools
320 - Political science
363 - Other social problems & services
333 - Economics of land & energy
7
170 - Ethics
5
700 - The arts; fine & decorative arts
4
330 - Economics
3
340 - Law
3
551 - Geology, hydrology & meteorology
3
581 - Specific topics in natural history
3
200 - Religion
2
300 - Social sciences
1
301 - Sociology & anthropology
1
304 - Factors affecting social behavior
1
370 - Education
1
600 - Technology
1
610 - Medicine & health
1
620 - Engineering & allied operations
1
900 - History & geography
1