Classification
330 - Economics
30
320 - Political science
20
333 - Economics of land & energy
17
630 - Agriculture & related technologies
13
336 - Public finance
11
363 - Other social problems & services
9
600 - Technology
9
370 - Education
8
380 - Commerce, communications & transportation
7
304 - Factors affecting social behavior
3
610 - Medicine & health
3