@book { DerZahlungsverkehr,
    title = "Der Zahlungsverkehr",
    author = "Lutz {Völker} and Jörg {Herold} and Uwe {Lehmann}",
    year = "2014",
    publisher = "GRIN Verlag",
    address = "München, Germany",
    url = "https://www.hausarbeiten.de/document/284763"
}