Classification
320 - Political science
330 - Economics
333 - Economics of land & energy
380 - Commerce, communications & transportation
600 - Technology
900 - History & geography
700 - The arts; fine & decorative arts
6
363 - Other social problems & services
4
551 - Geology, hydrology & meteorology
4
620 - Engineering & allied operations
4
370 - Education
3
610 - Medicine & health
3
720 - Architecture
3
000 - Computer science, information & general works
2
580 - Plants (Botany)
2
140 - Specific philosophical schools
1
304 - Factors affecting social behavior
1
340 - Law
1
581 - Specific topics in natural history
1
658 - General management
1