Classification
540 - Chemistry & allied sciences
580 - Plants (Botany)
610 - Medicine & health
700 - The arts; fine & decorative arts
330 - Economics
1
333 - Economics of land & energy
1
363 - Other social problems & services
1
530 - Physics
1
600 - Technology
1
620 - Engineering & allied operations
1
900 - History & geography
1