Classification
551 - Geology, hydrology & meteorology
600 - Technology
620 - Engineering & allied operations
9
363 - Other social problems & services
7
900 - History & geography
5
700 - The arts; fine & decorative arts
4
500 - Natural sciences & mathematics
3
140 - Specific philosophical schools
2
330 - Economics
2
590 - Animals (Zoology)
2
000 - Computer science, information & general works
1
400 - Language
1
530 - Physics
1
540 - Chemistry & allied sciences
1
550 - Earth sciences
1
581 - Specific topics in natural history
1
630 - Agriculture & related technologies
1