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