Classification
300 - Social sciences
330 - Economics
363 - Other social problems & services
320 - Political science
21
333 - Economics of land & energy
16
600 - Technology
14
551 - Geology, hydrology & meteorology
9
581 - Specific topics in natural history
9
900 - History & geography
9
700 - The arts; fine & decorative arts
8
140 - Specific philosophical schools
7
380 - Commerce, communications & transportation
7
610 - Medicine & health
7
370 - Education
6
000 - Computer science, information & general works
5
100 - Philosophy & psychology
5
301 - Sociology & anthropology
5
620 - Engineering & allied operations
4
170 - Ethics
3
340 - Law
3
576 - Genetics & evolution
3
630 - Agriculture & related technologies
3
200 - Religion
2
304 - Factors affecting social behavior
2
400 - Language
2
500 - Natural sciences & mathematics
2
658 - General management
2
302 - Social interaction
1
350 - Public administration & military science
1
580 - Plants (Botany)
1
650 - Management & auxiliary services
1
657 - Accounting
1