@book { MarketinganffentlichenBhnen,
    title = "Marketing an öffentlichen Bühnen.",
    author = "Christian {Decker}",
    year = "2006",
    publisher = "GRIN Verlag",
    address = "München, Germany",
    doi = "10.3239/9783638490290",
    url = "https://www.hausarbeiten.de/document/53633"
}