Classification
333 - Economics of land & energy
370 - Education
800 - Literature & rhetoric
900 - History & geography
4
600 - Technology
3
700 - The arts; fine & decorative arts
3
363 - Other social problems & services
2
100 - Philosophy & psychology
1
300 - Social sciences
1
330 - Economics
1
380 - Commerce, communications & transportation
1
400 - Language
1
530 - Physics
1
551 - Geology, hydrology & meteorology
1
581 - Specific topics in natural history
1
610 - Medicine & health
1
620 - Engineering & allied operations
1
658 - General management
1
720 - Architecture
1