Classification
140 - Specific philosophical schools
380 - Commerce, communications & transportation
581 - Specific topics in natural history
600 - Technology
700 - The arts; fine & decorative arts
363 - Other social problems & services
4
320 - Political science
3
361 - Social problems & social welfare in general
3
620 - Engineering & allied operations
3
900 - History & geography
3
000 - Computer science, information & general works
2
200 - Religion
2
301 - Sociology & anthropology
1
330 - Economics
1
333 - Economics of land & energy
1
551 - Geology, hydrology & meteorology
1
576 - Genetics & evolution
1
630 - Agriculture & related technologies
1