Classification
UED - Environmental policy
271
UMV - Climatic change
101
UEA - Environmental policy and economy - general aspects
63
UCA - Environmental problems, man and environment - general aspects
53
UEN - Environmental economy
26
UEF - Sustainability
24
LCK - Ecology - general aspects
19
YRA - Social studies
19
UEG - Environmental programs and expertises
18
UHP - Protection of nature and landscape
18
YRC - Technology and society
18
UCN - Environmental education
15
UKA - Environmental damage and energy production
15
EXA - Energy policy
14
YPO - Economic policy
12
UCE - Environmental impact, environmental pollution
10
UCJ - Environmental protection - general aspects
10
YEA - Environmental law
9
UAA - Environment - reference books
8
UHC - Area planning and environment
8
UCL - Environmental research
7
UAD - Environment - comprehensive works
6
UCG - Control of environmental pollution
6
UEDM - Policy of clean air
6
UHN - Landscape ecology
6
YPB - Economy - general aspects
6
YZA - Politics, political science
6
UMK - Air pollution - general aspects
5
UPN - Water protection, water quality, clean water
5
UAN - Environment - mathematical methods, computer applications
4
UHK - Traffic and environment - incl. automobile exhaust gas
4
UPC - Water - general aspects
4
USG - Waste treatment, waste disposal
4
USU - Waste recycling
4
GWA - Raw material economy, raw material policy
3
HYE - Environmental health
3
UAM - Environmental models
3
UCQ - Environmental technology
3
UKE - Environment and energy resources
3
UMEE - Clean air planning
3
UMN - Air pollution control and measurement
3
UPK - Water resources, water supply
3
UPVN - Ocean water, coastal waters
3
USGP - Waste treatment - other methods
3
USGT - Waste prevention
3
UVC - Environmental chemicals, hazardous materials - general aspects
3
YRB - Social sciences, sociology
3
YRE - Risk assessment
3
AHPC - Ethics
2
EHA - Renewable energy sources
2
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