@book { DieKonkurrenzforschungimstrategischenManagement,
    title = "Die Konkurrenzforschung im strategischen Management",
    author = "Friedrich {Weigmann}",
    year = "2003",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    doi = "10.3239/9783832464752",
    url = "https://m.diplom.de/document/221895"
}