Classification
333 - Economics of land & energy
707
363 - Other social problems & services
572
330 - Economics
552
320 - Political science
509
370 - Education
444
304 - Factors affecting social behavior
281
610 - Medicine & health
281
336 - Public finance
192
600 - Technology
153
380 - Commerce, communications & transportation
148
630 - Agriculture & related technologies
121
340 - Law
1