Classification
UEN - Environmental economy
8
UAM - Environmental models
2
UEF - Sustainability
2
YPGB - Process management
2
EWA - Energy economy
1
UCA - Environmental problems, man and environment - general aspects
1
UCE - Environmental impact, environmental pollution
1
UCEA - Environmental impact
1
UED - Environmental policy
1
USU - Waste recycling
1
YRC - Technology and society
1