@book { HerrFrhlichrettetWeihnachten,
    title = "Herr Fröhlich rettet Weihnachten",
    author = "Folko {Hülsebusch}",
    year = "2012",
    publisher = "dotbooks Verlag",
    address = "München, Deutschland",
    doi = "10.3239/9783955200541",
    url = "https://m.dotbooks.de/document/204520"
}