Classification
600 - Technology
140 - Specific philosophical schools
2
330 - Economics
2
363 - Other social problems & services
2
620 - Engineering & allied operations
2
700 - The arts; fine & decorative arts
2
100 - Philosophy & psychology
1
200 - Religion
1
300 - Social sciences
1
301 - Sociology & anthropology
1
320 - Political science
1
333 - Economics of land & energy
1
380 - Commerce, communications & transportation
1
530 - Physics
1
581 - Specific topics in natural history
1
630 - Agriculture & related technologies
1
900 - History & geography
1