Classification
551 - Geology, hydrology & meteorology
700 - The arts; fine & decorative arts
900 - History & geography
600 - Technology
40
620 - Engineering & allied operations
36
363 - Other social problems & services
27
333 - Economics of land & energy
21
380 - Commerce, communications & transportation
14
320 - Political science
13
330 - Economics
12
000 - Computer science, information & general works
11
140 - Specific philosophical schools
9
610 - Medicine & health
9
720 - Architecture
5
370 - Education
4
530 - Physics
4
580 - Plants (Botany)
4
581 - Specific topics in natural history
4
576 - Genetics & evolution
3
630 - Agriculture & related technologies
3
340 - Law
2
360 - Social problems & services; associations
2
500 - Natural sciences & mathematics
2
800 - Literature & rhetoric
2
170 - Ethics
1
300 - Social sciences
1
361 - Social problems & social welfare in general
1
400 - Language
1
414 - Phonology & phonetics
1
540 - Chemistry & allied sciences
1