D - History (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
For more detailed information, visit the Library of Congress Classification Outline.
D - History (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