@book { AnalysederKundenzufriedenheitimExpregutmarkt,
    title = "Analyse der Kundenzufriedenheit im Expreßgutmarkt",
    author = "Alexander {Woitas}",
    year = "1997",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    doi = "10.3239/9783832403690",
    url = "https://m.diplom.de/document/216349"
}