@book { SponsoringimProfifuballDasBeispieladidas,
    title = "Sponsoring im Profifußball: Das Beispiel adidas",
    author = "Andreas {Heiden}",
    year = "2015",
    publisher = "BACHELOR + MASTER PUBLISHING",
    address = "Hamburg, Deutschland",
    url = "https://m.bachelor-master-publishing.de/document/297883"
}