Classification
330 - Economics
22
900 - History & geography
20
320 - Political science
18
610 - Medicine & health
16
304 - Factors affecting social behavior
15
370 - Education
12
000 - Computer science, information & general works
8
340 - Law
8
363 - Other social problems & services
7
414 - Phonology & phonetics
6
551 - Geology, hydrology & meteorology
6
700 - The arts; fine & decorative arts
6
400 - Language
5
333 - Economics of land & energy
4
336 - Public finance
4
600 - Technology
4
380 - Commerce, communications & transportation
3
100 - Philosophy & psychology
2
140 - Specific philosophical schools
2
361 - Social problems & social welfare in general
2
540 - Chemistry & allied sciences
2
620 - Engineering & allied operations
2
720 - Architecture
2
791 - Public performances
2
820 - English & Old English literatures
2
949 - Other parts of Europe
2
170 - Ethics
1
300 - Social sciences
1
303 - Social processes
1
331 - Labor economics
1
352 - General considerations of public administration
1
362 - Social welfare problems & services
1
364 - Criminology
1
410 - Linguistics
1
550 - Earth sciences
1
576 - Genetics & evolution
1
581 - Specific topics in natural history
1
800 - Literature & rhetoric
1
891 - East Indo-European & Celtic literatures
1
940 - History of Europe
1