@book { PDFWorkflowinderDruckvorstufe,
    title = "PDF Workflow in der Druckvorstufe",
    author = "Thomas {Schubert}",
    year = "2002",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    doi = "10.3239/9783832449773",
    url = "https://m.diplom.de/document/220542"
}