@book { CustomerSatisfactionMeasurementontheInternet,
    title = "Customer Satisfaction Measurement on the Internet",
    author = "Katja {Hofmaier}",
    year = "1999",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    doi = "10.3239/9783832415808",
    url = "https://m.diplom.de/document/217420"
}