Classification
140 - Specific philosophical schools
333 - Economics of land & energy
600 - Technology
620 - Engineering & allied operations
21
700 - The arts; fine & decorative arts
21
363 - Other social problems & services
20
330 - Economics
15
900 - History & geography
14
380 - Commerce, communications & transportation
12
000 - Computer science, information & general works
10
610 - Medicine & health
9
630 - Agriculture & related technologies
8
580 - Plants (Botany)
7
320 - Political science
6
300 - Social sciences
5
340 - Law
5
720 - Architecture
5
170 - Ethics
4
551 - Geology, hydrology & meteorology
4
576 - Genetics & evolution
4
370 - Education
3
500 - Natural sciences & mathematics
3
530 - Physics
3
100 - Philosophy & psychology
2
304 - Factors affecting social behavior
2
400 - Language
2
581 - Specific topics in natural history
2
800 - Literature & rhetoric
2
120 - Epistemology, causation & humankind
1
200 - Religion
1
301 - Sociology & anthropology
1
361 - Social problems & social welfare in general
1
410 - Linguistics
1
540 - Chemistry & allied sciences
1
657 - Accounting
1
770 - Photography, photographs & computer art
1
780 - Music
1