COWI Consulting Engineers and Planners AS. (1999). Economic instruments in environmental protection in Denmark. Denmark: Ministry of Environment and Energy.
Παραπομπή Chicago StyleCOWI Consulting Engineers and Planners AS. Economic Instruments in Environmental Protection in Denmark. Denmark: Ministry of Environment and Energy, 1999.
Παραπομπή MLACOWI Consulting Engineers and Planners AS. Economic Instruments in Environmental Protection in Denmark. Denmark: Ministry of Environment and Energy, 1999.
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