Classification
320 - Political science
330 - Economics
333 - Economics of land & energy
363 - Other social problems & services
600 - Technology
551 - Geology, hydrology & meteorology
2
581 - Specific topics in natural history
2
620 - Engineering & allied operations
2
630 - Agriculture & related technologies
2
140 - Specific philosophical schools
1
300 - Social sciences
1
576 - Genetics & evolution
1
700 - The arts; fine & decorative arts
1