@book { ErsetzenKreditkartenZentralbankgeld,
    title = "Ersetzen Kreditkarten Zentralbankgeld?",
    author = "Simon {Bokämper}",
    year = "1999",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    doi = "10.3239/9783832413996",
    url = "https://m.diplom.de/document/217260"
}