Classification
330 - Economics
2
333 - Economics of land & energy
2
363 - Other social problems & services
2
581 - Specific topics in natural history
630 - Agriculture & related technologies
140 - Specific philosophical schools
1
320 - Political science
1
340 - Law
1
580 - Plants (Botany)
1
600 - Technology
1
610 - Medicine & health
1
620 - Engineering & allied operations
1