Classification
330 - Economics
363 - Other social problems & services
380 - Commerce, communications & transportation
576 - Genetics & evolution
600 - Technology
000 - Computer science, information & general works
5
333 - Economics of land & energy
5
140 - Specific philosophical schools
4
700 - The arts; fine & decorative arts
4
320 - Political science
3
620 - Engineering & allied operations
3
340 - Law
2
370 - Education
2
551 - Geology, hydrology & meteorology
2
581 - Specific topics in natural history
2
657 - Accounting
2
658 - General management
2
900 - History & geography
2
400 - Language
1
610 - Medicine & health
1
630 - Agriculture & related technologies
1
720 - Architecture
1