Classification
380 - Commerce, communications & transportation
620 - Engineering & allied operations
600 - Technology
9
700 - The arts; fine & decorative arts
8
900 - History & geography
8
000 - Computer science, information & general works
6
140 - Specific philosophical schools
6
363 - Other social problems & services
6
333 - Economics of land & energy
4
330 - Economics
3
370 - Education
3
400 - Language
2
500 - Natural sciences & mathematics
2
551 - Geology, hydrology & meteorology
2
580 - Plants (Botany)
2
720 - Architecture
2
340 - Law
1
530 - Physics
1
610 - Medicine & health
1
612 - Human physiology
1
780 - Music
1
800 - Literature & rhetoric
1