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