Classification
330 - Economics
320 - Political science
810
304 - Factors affecting social behavior
698
610 - Medicine & health
698
333 - Economics of land & energy
607
600 - Technology
415
363 - Other social problems & services
389
370 - Education
264
380 - Commerce, communications & transportation
186
336 - Public finance
134
630 - Agriculture & related technologies
78
340 - Law
3