Classification
900 - History & geography
370 - Education
13
600 - Technology
10
333 - Economics of land & energy
7
363 - Other social problems & services
7
140 - Specific philosophical schools
6
330 - Economics
6
400 - Language
6
700 - The arts; fine & decorative arts
6
620 - Engineering & allied operations
5
000 - Computer science, information & general works
4
380 - Commerce, communications & transportation
4
100 - Philosophy & psychology
3
320 - Political science
3
720 - Architecture
3
800 - Literature & rhetoric
3
170 - Ethics
2
410 - Linguistics
2
630 - Agriculture & related technologies
2
160 - Logic
1
200 - Religion
1
304 - Factors affecting social behavior
1
500 - Natural sciences & mathematics
1
530 - Physics
1
540 - Chemistry & allied sciences
1
551 - Geology, hydrology & meteorology
1
576 - Genetics & evolution
1
580 - Plants (Botany)
1
610 - Medicine & health
1
658 - General management
1