Classification
UED - Environmental policy
74
UCA - Environmental problems, man and environment - general aspects
72
UCJ - Environmental protection - general aspects
49
YUD - Comprehensive statistical data - Germany
48
UHP - Protection of nature and landscape
42
UEA - Environmental policy and economy - general aspects
34
YZA - Politics, political science
29
YPB - Economy - general aspects
27
UMV - Climatic change
26
UEN - Environmental economy
22
UEG - Environmental programs and expertises
20
UCN - Environmental education
19
UCQ - Environmental technology
19
UAA - Environment - reference books
18
AZZ - Firm index - general
17
UAD - Environment - comprehensive works
17
YUC - Comprehensive statistical data
17
LCK - Ecology - general aspects
15
UCE - Environmental impact, environmental pollution
15
UCL - Environmental research
14
UHN - Landscape ecology
14
URA - Soil chemistry
14
UVC - Environmental chemicals, hazardous materials - general aspects
14
EVA - Energy demand, energy supply - comprehensive works
12
YRC - Technology and society
11
GWA - Raw material economy, raw material policy
10
UCG - Control of environmental pollution
9
UCS - Environmental chemistry
9
UHC - Area planning and environment
9
UKA - Environmental damage and energy production
9
UXN - Radiation protection in nuclear facilities
9
UHK - Traffic and environment - incl. automobile exhaust gas
8
USG - Waste treatment, waste disposal
7
YRA - Social studies
7
UPVN - Ocean water, coastal waters
6
USGK - Waste incineration
6
YEA - Environmental law
6
AEG - Official corporations - Germany
5
EPK - Nuclear energy
5
LCM - Terrestrial ecology
5
UA - Environment - general
5
UAX - Environment - information systems, literature guides
5
UEND - Environmental costs, environmental investments
5
UKH - Environment and power plants, industrial plants
5
UXA - Environmental radioactivity
5
UXL - Radiation protection - general aspects
5
GBA - General geology, historical geology
4
LWE - Agriculture - general aspects
4
LWV - Agriculture - plant protection
4
UCEB - Environmental pollution
4
more ...