Classification
330 - Economics
75
304 - Factors affecting social behavior
54
610 - Medicine & health
54
320 - Political science
46
370 - Education
42
333 - Economics of land & energy
31
336 - Public finance
30
363 - Other social problems & services
16
600 - Technology
14
380 - Commerce, communications & transportation
12
630 - Agriculture & related technologies
4