@book { FreierJournalistoderangestellterRedakteur,
    title = "Freier Journalist oder angestellter Redakteur",
    author = "Wolfgang {Willems}",
    year = "1997",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    doi = "10.3239/9783832401702",
    url = "https://m.diplom.de/document/216121"
}