Classification
900 - History & geography
46
333 - Economics of land & energy
9
500 - Natural sciences & mathematics
9
600 - Technology
9
100 - Philosophy & psychology
8
620 - Engineering & allied operations
8
700 - The arts; fine & decorative arts
8
530 - Physics
7
800 - Literature & rhetoric
7
301 - Sociology & anthropology
5
540 - Chemistry & allied sciences
5
610 - Medicine & health
5
200 - Religion
4
300 - Social sciences
4
363 - Other social problems & services
4
400 - Language
4
320 - Political science
3
520 - Astronomy & allied sciences
3
140 - Specific philosophical schools
2
170 - Ethics
2
330 - Economics
2
410 - Linguistics
2
780 - Music
2
000 - Computer science, information & general works
1
340 - Law
1
370 - Education
1
380 - Commerce, communications & transportation
1
576 - Genetics & evolution
1
581 - Specific topics in natural history
1
630 - Agriculture & related technologies
1