Classification
300 - Social sciences
52
600 - Technology
51
330 - Economics
13
320 - Political science
11
610 - Medicine & health
10
900 - History & geography
8
301 - Sociology & anthropology
7
100 - Philosophy & psychology
6
363 - Other social problems & services
6
140 - Specific philosophical schools
5
380 - Commerce, communications & transportation
5
620 - Engineering & allied operations
5
000 - Computer science, information & general works
4
333 - Economics of land & energy
4
500 - Natural sciences & mathematics
4
700 - The arts; fine & decorative arts
4
370 - Education
3
551 - Geology, hydrology & meteorology
3
120 - Epistemology, causation & humankind
2
400 - Language
2
170 - Ethics
1
340 - Law
1
364 - Criminology
1
520 - Astronomy & allied sciences
1
540 - Chemistry & allied sciences
1
581 - Specific topics in natural history
1
630 - Agriculture & related technologies
1
800 - Literature & rhetoric
1
920 - Biography, genealogy & insignia
1