Classification
304 - Factors affecting social behavior
320 - Political science
292
330 - Economics
940
333 - Economics of land & energy
317
336 - Public finance
30
340 - Law
3
363 - Other social problems & services
136
370 - Education
209
380 - Commerce, communications & transportation
53
600 - Technology
123
610 - Medicine & health
2,482
630 - Agriculture & related technologies
33