@book { BilligfliegerimRaumEuropaEinestrategischeAnalyse,
    title = "Billigflieger im Raum Europa: Eine strategische Analyse",
    author = "Philipp Heinrich Claudius {Fischer}",
    year = "2013",
    publisher = "BACHELOR + MASTER PUBLISHING",
    address = "Hamburg, Deutschland",
    url = "https://m.bachelor-master-publishing.de/document/296749"
}