Classification
900 - History & geography
670
600 - Technology
606
610 - Medicine & health
570
320 - Political science
538
700 - The arts; fine & decorative arts
514
500 - Natural sciences & mathematics
463
300 - Social sciences
452
100 - Philosophy & psychology
432
330 - Economics
432
340 - Law
318
333 - Economics of land & energy
297
370 - Education
289
363 - Other social problems & services
258
005 - Computer programming, programs & data
251
200 - Religion
233
620 - Engineering & allied operations
231
006 - Special computer methods
229
304 - Factors affecting social behavior
223
800 - Literature & rhetoric
212
140 - Specific philosophical schools
208
621 - Applied physics
198
658 - General management
189
301 - Sociology & anthropology
169
400 - Language
160
000 - Computer science, information & general works
148
380 - Commerce, communications & transportation
128
170 - Ethics
106
530 - Physics
105
410 - Linguistics
96
616 - Diseases
78
551 - Geology, hydrology & meteorology
76
580 - Plants (Botany)
69
540 - Chemistry & allied sciences
64
630 - Agriculture & related technologies
64
720 - Architecture
64
581 - Specific topics in natural history
63
004 - Data processing & computer science
61
612 - Human physiology
60
780 - Music
53
629 - Other branches of engineering
48
361 - Social problems & social welfare in general
47
306 - Culture & institutions
46
297 - Islam, Babism & Bahai Faith
43
576 - Genetics & evolution
41
338 - Production
36
336 - Public finance
35
120 - Epistemology, causation & humankind
34
615 - Pharmacology & therapeutics
34
331 - Labor economics
33
364 - Criminology
30
more ...