Classification
304 - Factors affecting social behavior
343
610 - Medicine & health
330 - Economics
107
333 - Economics of land & energy
65
320 - Political science
64
370 - Education
27
600 - Technology
20
363 - Other social problems & services
16
630 - Agriculture & related technologies
11
380 - Commerce, communications & transportation
5
336 - Public finance
2