@book { DieMessungvonKundenzufriedenheit,
    title = "Die Messung von Kundenzufriedenheit",
    author = "Harald {Storr}",
    year = "2000",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    doi = "10.3239/9783832421540",
    url = "https://m.diplom.de/document/217985"
}