Classification
320 - Political science
340 - Law
363 - Other social problems & services
900 - History & geography
700 - The arts; fine & decorative arts
6
140 - Specific philosophical schools
5
333 - Economics of land & energy
5
330 - Economics
4
380 - Commerce, communications & transportation
4
600 - Technology
4
620 - Engineering & allied operations
4
720 - Architecture
4
500 - Natural sciences & mathematics
3
576 - Genetics & evolution
3
581 - Specific topics in natural history
3
630 - Agriculture & related technologies
3
100 - Philosophy & psychology
1
551 - Geology, hydrology & meteorology
1
580 - Plants (Botany)
1
657 - Accounting
1