@book { ControllinginderffentlichenVerwaltung,
    title = "Controlling in der öffentlichen Verwaltung",
    author = "Hanna {Hahn}",
    year = "2001",
    publisher = "GRIN Verlag",
    address = "München, Germany",
    doi = "10.3239/9783640012442",
    url = "https://www.hausarbeiten.de/document/102864"
}