Classification
000 - Computer science, information & general works
320 - Political science
600 - Technology
17
620 - Engineering & allied operations
333 - Economics of land & energy
15
700 - The arts; fine & decorative arts
13
900 - History & geography
13
330 - Economics
11
363 - Other social problems & services
9
380 - Commerce, communications & transportation
5
610 - Medicine & health
4
720 - Architecture
4
140 - Specific philosophical schools
3
300 - Social sciences
3
370 - Education
3
530 - Physics
3
658 - General management
3
551 - Geology, hydrology & meteorology
2
576 - Genetics & evolution
2
580 - Plants (Botany)
2
630 - Agriculture & related technologies
2
100 - Philosophy & psychology
1
170 - Ethics
1
361 - Social problems & social welfare in general
1
400 - Language
1
410 - Linguistics
1
500 - Natural sciences & mathematics
1
540 - Chemistry & allied sciences
1
581 - Specific topics in natural history
1
657 - Accounting
1
770 - Photography, photographs & computer art
1
780 - Music
1
800 - Literature & rhetoric
1