Classification
300 - Social sciences
21
320 - Political science
15
340 - Law
15
658 - General management
15
330 - Economics
12
900 - History & geography
8
610 - Medicine & health
7
616 - Diseases
7
770 - Photography, photographs & computer art
7
800 - Literature & rhetoric
6
158 - Applied psychology
5
650 - Management & auxiliary services
5
700 - The arts; fine & decorative arts
5
778 - Fields & kinds of photography
5
620 - Engineering & allied operations
4
004 - Data processing & computer science
3
100 - Philosophy & psychology
3
200 - Religion
3
301 - Sociology & anthropology
3
332 - Financial economics
3
570 - Life sciences; biology
3
830 - Literatures of Germanic languages
3
000 - Computer science, information & general works
2
150 - Psychology
2
302 - Social interaction
2
304 - Factors affecting social behavior
2
305 - Social groups
2
306 - Culture & institutions
2
339 - Macroeconomics & related topics
2
341 - Law of nations
2
361 - Social problems & social welfare in general
2
617 - Surgery & related medical specialties
2
629 - Other branches of engineering
2
808 - Rhetoric & collections of literature
2
001 - Knowledge
1
005 - Computer programming, programs & data
1
006 - Special computer methods
1
155 - Differential & developmental psychology
1
331 - Labor economics
1
338 - Production
1
351 - Public administration
1
370 - Education
1
371 - Schools & their activities; special education
1
372 - Elementary education
1
381 - Commerce
1
400 - Language
1
410 - Linguistics
1
500 - Natural sciences & mathematics
1
530 - Physics
1
540 - Chemistry & allied sciences
1
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