Classification
333 - Economics of land & energy
363 - Other social problems & services
530 - Physics
600 - Technology
620 - Engineering & allied operations
500 - Natural sciences & mathematics
3
700 - The arts; fine & decorative arts
3
900 - History & geography
3
000 - Computer science, information & general works
2
370 - Education
2
540 - Chemistry & allied sciences
2
551 - Geology, hydrology & meteorology
2
630 - Agriculture & related technologies
2
140 - Specific philosophical schools
1
300 - Social sciences
1
320 - Political science
1
330 - Economics
1
380 - Commerce, communications & transportation
1
576 - Genetics & evolution
1
580 - Plants (Botany)
1
581 - Specific topics in natural history
1
610 - Medicine & health
1
800 - Literature & rhetoric
1