Classification
140 - Specific philosophical schools
361 - Social problems & social welfare in general
380 - Commerce, communications & transportation
600 - Technology
5
320 - Political science
4
700 - The arts; fine & decorative arts
4
000 - Computer science, information & general works
3
200 - Religion
3
363 - Other social problems & services
3
581 - Specific topics in natural history
3
330 - Economics
2
333 - Economics of land & energy
2
610 - Medicine & health
2
170 - Ethics
1
301 - Sociology & anthropology
1
304 - Factors affecting social behavior
1
336 - Public finance
1
370 - Education
1
551 - Geology, hydrology & meteorology
1
580 - Plants (Botany)
1
620 - Engineering & allied operations
1
630 - Agriculture & related technologies
1
658 - General management
1
800 - Literature & rhetoric
1
900 - History & geography
1