Classification
UMNE - Air pollution by gaseous pollutants
25
UED - Environmental policy
20
AED - Official corporations - international and supranational
19
YMG - Law of international and supranational organizations
14
EXA - Energy policy
12
YMA - International law
11
UMV - Climatic change
8
YZA - Politics, political science
7
AHA - Research and development, research politics - general
5
YEA - Environmental law
5
YEM - Energy law
5
YNA - Patents, trademarks
5
YPM - National economy
5
AHF - Research and science
4
EVN - Energy supply - future aspects
4
EWA - Energy economy
4
YAA - Law, economy, social affairs - reference books
4
YPD - Business economics
4
YPO - Economic policy
4
EBA - Energy production, energy technology
3
EHA - Renewable energy sources
3
UMGE - Carbon capture and storage (CCS)
3
AAE - Popular science - general aspects
2
AEK - Official corporations - Europe
2
AHE - Research and development, research politics - foreign countries
2
HYB - Public health, health politics
2
LTA - Biotechnology - reference books
2
LVN - Food science - chemistry, analytics
2
UCA - Environmental problems, man and environment - general aspects
2
UEG - Environmental programs and expertises
2
UKA - Environmental damage and energy production
2
YBB - Law - general
2
YCE - Federal constitutional law
2
YDM - Commercial law, commercial legislation
2
YDZ - Data protection law
2
YEC - Law on waters
2
YPB - Economy - general aspects
2
ZCC - Information technology
2
ABA - General international and supranational biographic catalogues
1
ACE - Germanic languages, Indo-Germanic languages
1
AHC - Research and development, research politics - Germany
1
AHN - Media and communication science
1
AHPC - Ethics
1
ASCJ - Library catalog
1
DNC - Internet
1
DWI - Information management
1
DZE - Data privacy, data security
1
EIP - Photovoltaics
1
GRB - Climatology
1
HAA - Medicine - reference books
1
more ...