Classification
170 - Ethics
330 - Economics
333 - Economics of land & energy
363 - Other social problems & services
140 - Specific philosophical schools
6
100 - Philosophy & psychology
4
320 - Political science
4
581 - Specific topics in natural history
4
700 - The arts; fine & decorative arts
4
551 - Geology, hydrology & meteorology
3
600 - Technology
3
620 - Engineering & allied operations
3
900 - History & geography
3
000 - Computer science, information & general works
2
200 - Religion
2
340 - Law
1
380 - Commerce, communications & transportation
1
610 - Medicine & health
1
630 - Agriculture & related technologies
1
720 - Architecture
1