@book { SportsponsoringalsInstrumentdesCustomerRelationshipManagementCRM,
    title = "Sportsponsoring als Instrument des Customer Relationship Management (CRM)",
    author = "Fabian {Mottl}",
    year = "2009",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    doi = "10.3239/9783836629058",
    url = "https://m.diplom.de/document/226758"
}