Classification
580 - Plants (Botany)
620 - Engineering & allied operations
7
000 - Computer science, information & general works
6
630 - Agriculture & related technologies
6
600 - Technology
5
610 - Medicine & health
5
333 - Economics of land & energy
4
700 - The arts; fine & decorative arts
4
363 - Other social problems & services
3
380 - Commerce, communications & transportation
3
100 - Philosophy & psychology
2
330 - Economics
2
576 - Genetics & evolution
2
581 - Specific topics in natural history
2
500 - Natural sciences & mathematics
1
800 - Literature & rhetoric
1
900 - History & geography
1