Classification
900 - History & geography
45
320 - Political science
36
300 - Social sciences
20
100 - Philosophy & psychology
7
330 - Economics
6
410 - Linguistics
6
700 - The arts; fine & decorative arts
6
800 - Literature & rhetoric
6
340 - Law
5
400 - Language
5
370 - Education
4
380 - Commerce, communications & transportation
4
363 - Other social problems & services
3
576 - Genetics & evolution
3
140 - Specific philosophical schools
2
200 - Religion
2
304 - Factors affecting social behavior
2
333 - Economics of land & energy
2
414 - Phonology & phonetics
2
610 - Medicine & health
2
780 - Music
2
791 - Public performances
2