Classification
100 - Philosophy & psychology
140 - Specific philosophical schools
330 - Economics
700 - The arts; fine & decorative arts
333 - Economics of land & energy
4
170 - Ethics
3
320 - Political science
3
363 - Other social problems & services
3
600 - Technology
3
620 - Engineering & allied operations
3
610 - Medicine & health
2
200 - Religion
1
304 - Factors affecting social behavior
1
340 - Law
1
370 - Education
1
380 - Commerce, communications & transportation
1
581 - Specific topics in natural history
1
630 - Agriculture & related technologies
1
800 - Literature & rhetoric
1
900 - History & geography
1