@book { PotentialedesOnetoOneMarketingfrdenECommerce,
    title = "Potentiale des One-to-One Marketing für den E-Commerce",
    author = "Jan-Thomas {Nielsen}",
    year = "2002",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    doi = "10.3239/9783832455903",
    url = "https://m.diplom.de/document/221076"
}