@book { KonkurrenzanalysealsNavigationssystem,
    title = "Konkurrenzanalyse als Navigationssystem",
    author = "Anne {Leuschner}",
    year = "2010",
    publisher = "GRIN Verlag",
    address = "München, Germany",
    doi = "10.3239/9783640539260",
    url = "https://www.hausarbeiten.de/document/142772"
}