Classification
900 - History & geography
518
320 - Political science
108
909 - World history
78
300 - Social sciences
49
330 - Economics
41
200 - Religion
33
306 - Culture & institutions
29
700 - The arts; fine & decorative arts
29
800 - Literature & rhetoric
27
940 - History of Europe
22
100 - Philosophy & psychology
20
910 - Geography & travel
20
301 - Sociology & anthropology
16
140 - Specific philosophical schools
15
304 - Factors affecting social behavior
15
333 - Economics of land & energy
15
380 - Commerce, communications & transportation
14
600 - Technology
13
370 - Education
12
780 - Music
12
327 - International relations
11
340 - Law
11
297 - Islam, Babism & Bahai Faith
10
325 - International migration & colonization
10
610 - Medicine & health
10
941 - British Isles
10
000 - Computer science, information & general works
9
400 - Language
8
576 - Genetics & evolution
8
620 - Engineering & allied operations
8
930 - History of ancient world to ca. 499
8
410 - Linguistics
7
630 - Agriculture & related technologies
7
355 - Military science
6
363 - Other social problems & services
6
720 - Architecture
6
305 - Social groups
5
809 - History, description & criticism
5
950 - History of Asia; Far East
5
960 - History of Africa
5
338 - Production
4
361 - Social problems & social welfare in general
4
509 - Historical, geographic & persons treatment
4
170 - Ethics
3
500 - Natural sciences & mathematics
3
658 - General management
3
820 - English & Old English literatures
3
907 - Education, research & related topics
3
973 - United States
3
296 - Judaism
2
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