@book { SocialMarketinginderSozialwirtschaft,
    title = "Social Marketing in der Sozialwirtschaft",
    author = "Eike Christian {Reinfelder}",
    year = "2005",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    doi = "10.3239/9783832491826",
    url = "https://m.diplom.de/document/224308"
}