Classification
363 - Other social problems & services
628 - Sanitary & municipal engineering
65
344 - Labor, social, education & cultural law
44
327 - International relations
13
320 - Political science
8
330 - Economics
5
333 - Economics of land & energy
5
602 - Miscellany
4
610 - Medicine & health
4
304 - Factors affecting social behavior
3
340 - Law
3
696 - Utilities
3
900 - History & geography
3
380 - Commerce, communications & transportation
2
331 - Labor economics
1
336 - Public finance
1
500 - Natural sciences & mathematics
1
551 - Geology, hydrology & meteorology
1
600 - Technology
1
700 - The arts; fine & decorative arts
1
949 - Other parts of Europe
1