Classification
000 - Computer science, information & general works
5
333 - Economics of land & energy
630 - Agriculture & related technologies
700 - The arts; fine & decorative arts
4
363 - Other social problems & services
3
600 - Technology
3
620 - Engineering & allied operations
3
330 - Economics
2
580 - Plants (Botany)
2
610 - Medicine & health
2
380 - Commerce, communications & transportation
1
414 - Phonology & phonetics
1
551 - Geology, hydrology & meteorology
1