Classification
LCK - Ecology - general aspects
10
UED - Environmental policy
7
UCA - Environmental problems, man and environment - general aspects
5
UCN - Environmental education
2
UEA - Environmental policy and economy - general aspects
2
UEF - Sustainability
2
UHP - Protection of nature and landscape
2
USGT - Waste prevention
2
AFK - Research institutions - Germany
1
AHPC - Ethics
1
EXA - Energy policy
1
GPA - Geobiology - general
1
LCD - Ecology - comprensive works
1
LCO - Hydrobiology
1
UCE - Environmental impact, environmental pollution
1
UEN - Environmental economy
1
UEND - Environmental costs, environmental investments
1
UHC - Area planning and environment
1
UHN - Landscape ecology
1
UMT - Acid rain and atmospheric deposition
1
UVA - Environmental chemicals, hazardous materials - comprehensive works
1
YEA - Environmental law
1
YPO - Economic policy
1
YRB - Social sciences, sociology
1