Classification
300 - Social sciences
154
320 - Political science
73
600 - Technology
61
330 - Economics
49
900 - History & geography
46
500 - Natural sciences & mathematics
35
100 - Philosophy & psychology
20
305 - Social groups
20
363 - Other social problems & services
18
700 - The arts; fine & decorative arts
18
370 - Education
17
140 - Specific philosophical schools
16
301 - Sociology & anthropology
16
304 - Factors affecting social behavior
16
610 - Medicine & health
12
303 - Social processes
11
306 - Culture & institutions
11
333 - Economics of land & energy
11
340 - Law
11
658 - General management
10
302 - Social interaction
9
000 - Computer science, information & general works
8
338 - Production
8
670 - Manufacturing
7
720 - Architecture
5
200 - Religion
4
307 - Communities
4
327 - International relations
4
331 - Labor economics
4
520 - Astronomy & allied sciences
4
980 - History of South America
4
121 - Epistemology
3
155 - Differential & developmental psychology
3
158 - Applied psychology
3
321 - Systems of governments & states
3
380 - Commerce, communications & transportation
3
620 - Engineering & allied operations
3
800 - Literature & rhetoric
3
016 - Bibliographies of works on specific subjects
2
070 - News media, journalism & publishing
2
170 - Ethics
2
193 - Philosophy of Germany & Austria
2
308 - [Unassigned]
2
339 - Macroeconomics & related topics
2
364 - Criminology
2
509 - Historical, geographic & persons treatment
2
551 - Geology, hydrology & meteorology
2
580 - Plants (Botany)
2
581 - Specific topics in natural history
2
630 - Agriculture & related technologies
2
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