@book { GesetzlicheMindestlhneProundContra,
    title = "Gesetzliche Mindestlöhne: Pro und Contra",
    author = "Olga {Richter}",
    year = "2011",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    doi = "10.3239/9783842815698",
    url = "https://m.diplom.de/document/228534"
}