Classification
720 - Architecture
300 - Social sciences
13
320 - Political science
12
900 - History & geography
10
700 - The arts; fine & decorative arts
9
330 - Economics
8
600 - Technology
7
333 - Economics of land & energy
5
620 - Engineering & allied operations
5
100 - Philosophy & psychology
4
000 - Computer science, information & general works
3
380 - Commerce, communications & transportation
3
610 - Medicine & health
3
770 - Photography, photographs & computer art
3
140 - Specific philosophical schools
2
304 - Factors affecting social behavior
2
370 - Education
2
551 - Geology, hydrology & meteorology
2
780 - Music
2
301 - Sociology & anthropology
1
302 - Social interaction
1
363 - Other social problems & services
1
384 - Communications; telecommunication
1
398 - Folklore
1
410 - Linguistics
1
530 - Physics
1
696 - Utilities
1
800 - Literature & rhetoric
1