Classification
140 - Specific philosophical schools
581 - Specific topics in natural history
12
363 - Other social problems & services
11
320 - Political science
6
333 - Economics of land & energy
5
330 - Economics
4
700 - The arts; fine & decorative arts
4
100 - Philosophy & psychology
3
300 - Social sciences
3
170 - Ethics
2
340 - Law
2
500 - Natural sciences & mathematics
2
551 - Geology, hydrology & meteorology
2
600 - Technology
2
620 - Engineering & allied operations
2
900 - History & geography
2
200 - Religion
1
610 - Medicine & health
1
630 - Agriculture & related technologies
1
720 - Architecture
1
800 - Literature & rhetoric
1