Classification
333 - Economics of land & energy
5
363 - Other social problems & services
5
576 - Genetics & evolution
600 - Technology
630 - Agriculture & related technologies
580 - Plants (Botany)
4
620 - Engineering & allied operations
4
380 - Commerce, communications & transportation
3
700 - The arts; fine & decorative arts
3
140 - Specific philosophical schools
2
170 - Ethics
2
300 - Social sciences
2
330 - Economics
2
340 - Law
2
610 - Medicine & health
2
720 - Architecture
2
800 - Literature & rhetoric
2
900 - History & geography
2
000 - Computer science, information & general works
1
304 - Factors affecting social behavior
1
320 - Political science
1
370 - Education
1
551 - Geology, hydrology & meteorology
1
581 - Specific topics in natural history
1