Classification
330 - Economics
17
320 - Political science
12
305 - Social groups
8
900 - History & geography
7
300 - Social sciences
3
306 - Culture & institutions
3
333 - Economics of land & energy
3
370 - Education
3
140 - Specific philosophical schools
2
400 - Language
2
700 - The arts; fine & decorative arts
2
941 - British Isles
2
100 - Philosophy & psychology
1
200 - Religion
1
294 - Religions of Indic origin
1
297 - Islam, Babism & Bahai Faith
1
301 - Sociology & anthropology
1
307 - Communities
1
323 - Civil & political rights
1
339 - Macroeconomics & related topics
1
364 - Criminology
1
378 - Higher education
1
380 - Commerce, communications & transportation
1
420 - English & Old English
1
600 - Technology
1
780 - Music
1
800 - Literature & rhetoric
1
820 - English & Old English literatures
1
943 - Central Europe; Germany
1
954 - South Asia; India
1
974 - Northeastern United States
1