Classification
330 - Economics
9
630 - Agriculture & related technologies
8
320 - Political science
6
600 - Technology
3
620 - Engineering & allied operations
3
000 - Computer science, information & general works
2
333 - Economics of land & energy
2
380 - Commerce, communications & transportation
2
301 - Sociology & anthropology
1
331 - Labor economics
1
334 - Cooperatives
1
363 - Other social problems & services
1
551 - Geology, hydrology & meteorology
1
576 - Genetics & evolution
1
581 - Specific topics in natural history
1
700 - The arts; fine & decorative arts
1
900 - History & geography
1