Classification
370 - Education
304 - Factors affecting social behavior
14
330 - Economics
14
610 - Medicine & health
14
333 - Economics of land & energy
11
320 - Political science
8
600 - Technology
7
363 - Other social problems & services
2
336 - Public finance
1
380 - Commerce, communications & transportation
1
630 - Agriculture & related technologies
1