Classification
900 - History & geography
69
100 - Philosophy & psychology
30
410 - Linguistics
24
780 - Music
24
700 - The arts; fine & decorative arts
18
791 - Public performances
15
330 - Economics
13
300 - Social sciences
11
305 - Social groups
10
320 - Political science
10
398 - Folklore
8
331 - Labor economics
6
616 - Diseases
6
005 - Computer programming, programs & data
5
306 - Culture & institutions
5
333 - Economics of land & energy
5
658 - General management
5
004 - Data processing & computer science
4
301 - Sociology & anthropology
4
302 - Social interaction
4
340 - Law
4
380 - Commerce, communications & transportation
4
510 - Mathematics
4
511 - General principles of mathematics
4
515 - Analysis
4
000 - Computer science, information & general works
3
001 - Knowledge
3
006 - Special computer methods
3
190 - Modern western philosophy
3
304 - Factors affecting social behavior
3
338 - Production
3
339 - Macroeconomics & related topics
3
500 - Natural sciences & mathematics
3
539 - Modern physics
3
615 - Pharmacology & therapeutics
3
781 - General principles & musical forms
3
800 - Literature & rhetoric
3
930 - History of ancient world to ca. 499
3
016 - Bibliographies of works on specific subjects
2
140 - Specific philosophical schools
2
332 - Financial economics
2
371 - Schools & their activities; special education
2
501 - Philosophy & theory
2
519 - Probabilities & applied mathematics
2
530 - Physics
2
571 - Physiology & related subjects
2
610 - Medicine & health
2
809 - History, description & criticism
2
811 - American poetry in English
2
940 - History of Europe
2
more ...