Classification
330 - Economics
900 - History & geography
320 - Political science
3,873
576 - Genetics & evolution
375
700 - The arts; fine & decorative arts
371
300 - Social sciences
365
600 - Technology
275
340 - Law
250
620 - Engineering & allied operations
247
333 - Economics of land & energy
228
363 - Other social problems & services
135
380 - Commerce, communications & transportation
106
000 - Computer science, information & general works
103
370 - Education
74
610 - Medicine & health
68
630 - Agriculture & related technologies
66
100 - Philosophy & psychology
58
140 - Specific philosophical schools
56
200 - Religion
54
800 - Literature & rhetoric
47
580 - Plants (Botany)
43
720 - Architecture
38
551 - Geology, hydrology & meteorology
37
658 - General management
32
301 - Sociology & anthropology
28
170 - Ethics
25
400 - Language
25
500 - Natural sciences & mathematics
23
304 - Factors affecting social behavior
20
581 - Specific topics in natural history
17
780 - Music
15
414 - Phonology & phonetics
11
410 - Linguistics
10
530 - Physics
10
540 - Chemistry & allied sciences
10
160 - Logic
8
770 - Photography, photographs & computer art
7
350 - Public administration & military science
6
657 - Accounting
6
920 - Biography, genealogy & insignia
6
297 - Islam, Babism & Bahai Faith
5
336 - Public finance
5
361 - Social problems & social welfare in general
4
550 - Earth sciences
4
615 - Pharmacology & therapeutics
3
791 - Public performances
3
120 - Epistemology, causation & humankind
2
360 - Social problems & services; associations
2
520 - Astronomy & allied sciences
2
332 - Financial economics
1
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