D = World History (except North, Central and South American History)
D – General
DA – Great Britain
DAW – Central Europe
DB – Austria – Liechtenstein – Hungary – Czechoslovakia
DC – France – Andorra – Monaco
DD – Germany
DE – Greco-Roman World
DF – Greece
DG – Italy – Malta
DH – Low Countries –Benelux Countries
DJ – Netherlands (Holland)
DJK – Eastern Europe (General)
DK – Russia. Soviet Union. Former Soviet Republics-Poland
DL – Northern Europe-Scandinavia
DP – Spain-Portugal
DQ – Switzerland
DR – Balkan Peninsula
DS – Asia
DT – Africa
DU – Oceania (South Seas)
DX – Romanies
E = United States of America History
F = Local History of the United States, British, Dutch, French, and Latin America
F 1-975 - United States local history
F 1001-1145.2 - British America (including Canada), Dutch America
F 1170 - French America
F 1201-3799 - Latin America. Spanish America
