Classification
330 - Economics
53
900 - History & geography
320 - Political science
10
100 - Philosophy & psychology
9
300 - Social sciences
5
140 - Specific philosophical schools
4
333 - Economics of land & energy
4
340 - Law
4
363 - Other social problems & services
2
380 - Commerce, communications & transportation
2
630 - Agriculture & related technologies
2
800 - Literature & rhetoric
2
370 - Education
1
400 - Language
1
410 - Linguistics
1
551 - Geology, hydrology & meteorology
1
580 - Plants (Botany)
1
581 - Specific topics in natural history
1
610 - Medicine & health
1
700 - The arts; fine & decorative arts
1