Classification
320 - Political science
17
330 - Economics
14
333 - Economics of land & energy
9
304 - Factors affecting social behavior
3
610 - Medicine & health
3
370 - Education
2
380 - Commerce, communications & transportation
2
336 - Public finance
1
363 - Other social problems & services
1
600 - Technology
1
630 - Agriculture & related technologies
1