@book { EmissionshandelimLuftverkehr,
    title = "Emissionshandel im Luftverkehr",
    author = "Marcel {Otten}",
    year = "2007",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    doi = "10.3239/9783836604284",
    url = "https://m.diplom.de/document/228941"
}