Classification
333 - Economics of land & energy
704
363 - Other social problems & services
569
330 - Economics
544
320 - Political science
503
370 - Education
442
304 - Factors affecting social behavior
275
610 - Medicine & health
275
336 - Public finance
187
600 - Technology
152
380 - Commerce, communications & transportation
148
630 - Agriculture & related technologies
121
340 - Law
1