@book { InternetalsInstrumentderMarktforschung,
    title = "Internet als Instrument der Marktforschung",
    author = "Ralf {Reymann}",
    year = "2001",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    doi = "10.3239/9783832431969",
    url = "https://m.diplom.de/document/218890"
}