Vespermann, JanJanVespermannWittmer, AndreasAndreasWittmer2023-04-132023-04-132011-03https://www.alexandria.unisg.ch/handle/20.500.14171/9445810.1002/bse.683deEnvironmental policyEmissions tradingExternal costsTravel & TransportationAviationFinancial, Ecological and Managerial Impacts of Emission Trading Schemes : The Case of Lufthansajournal article