Classification
900 - History & geography
320 - Political science
2,331
330 - Economics
1,361
576 - Genetics & evolution
398
300 - Social sciences
308
700 - The arts; fine & decorative arts
235
340 - Law
208
100 - Philosophy & psychology
180
200 - Religion
122
800 - Literature & rhetoric
88
140 - Specific philosophical schools
76
333 - Economics of land & energy
65
301 - Sociology & anthropology
62
370 - Education
57
400 - Language
53
380 - Commerce, communications & transportation
52
600 - Technology
47
170 - Ethics
44
363 - Other social problems & services
44
000 - Computer science, information & general works
39
610 - Medicine & health
37
304 - Factors affecting social behavior
31
943 - Central Europe; Germany
30
780 - Music
26
620 - Engineering & allied operations
23
410 - Linguistics
21
297 - Islam, Babism & Bahai Faith
19
581 - Specific topics in natural history
18
350 - Public administration & military science
16
720 - Architecture
14
630 - Agriculture & related technologies
12
940 - History of Europe
12
120 - Epistemology, causation & humankind
11
296 - Judaism
11
551 - Geology, hydrology & meteorology
11
500 - Natural sciences & mathematics
10
361 - Social problems & social welfare in general
9
530 - Physics
9
770 - Photography, photographs & computer art
9
791 - Public performances
6
360 - Social problems & services; associations
5
364 - Criminology
5
305 - Social groups
4
322 - Relation of state to organized groups
4
324 - The political process
4
336 - Public finance
3
355 - Military science
3
580 - Plants (Botany)
3
160 - Logic
2
270 - History of Christianity & Christian church
2
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