Classification
330 - Economics
117
304 - Factors affecting social behavior
106
610 - Medicine & health
106
333 - Economics of land & energy
76
320 - Political science
72
363 - Other social problems & services
43
370 - Education
38
336 - Public finance
31
600 - Technology
27
380 - Commerce, communications & transportation
16
630 - Agriculture & related technologies
8