Classification
000 - Computer science, information & general works
380 - Commerce, communications & transportation
600 - Technology
900 - History & geography
700 - The arts; fine & decorative arts
9
620 - Engineering & allied operations
8
333 - Economics of land & energy
7
330 - Economics
6
363 - Other social problems & services
5
720 - Architecture
5
610 - Medicine & health
3
140 - Specific philosophical schools
2
400 - Language
2
576 - Genetics & evolution
2
320 - Political science
1
500 - Natural sciences & mathematics
1
551 - Geology, hydrology & meteorology
1
580 - Plants (Botany)
1