Classification
YPB - Economy - general aspects
39
YUD - Comprehensive statistical data - Germany
28
YUC - Comprehensive statistical data
19
YZA - Politics, political science
11
YDP - Foreign trade law, foreign currency law
9
YAD - Law, economy, social affairs - comprehensive works
2
ECA - Energy resources
1
EWA - Energy economy
1
GWBA - Raw material resources, raw material reserves
1
UED - Environmental policy
1
UEN - Environmental economy
1
YDM - Commercial law, commercial legislation
1
YPM - National economy
1
YPO - Economic policy
1
YPS - Economy of the developing countries
1
YRG - Technology transfer
1