Classification
300 - Social sciences
333 - Economics of land & energy
363 - Other social problems & services
9
330 - Economics
8
140 - Specific philosophical schools
7
581 - Specific topics in natural history
7
000 - Computer science, information & general works
6
610 - Medicine & health
6
620 - Engineering & allied operations
6
320 - Political science
5
630 - Agriculture & related technologies
5
700 - The arts; fine & decorative arts
5
380 - Commerce, communications & transportation
4
500 - Natural sciences & mathematics
4
551 - Geology, hydrology & meteorology
4
576 - Genetics & evolution
4
900 - History & geography
4
414 - Phonology & phonetics
3
540 - Chemistry & allied sciences
3
580 - Plants (Botany)
3
600 - Technology
3
612 - Human physiology
3
100 - Philosophy & psychology
2
301 - Sociology & anthropology
2
370 - Education
2
340 - Law
1
361 - Social problems & social welfare in general
1
400 - Language
1
658 - General management
1