@book { KarteninterpretationvonKarlsruheTK50,
    title = "Karteninterpretation von Karlsruhe (TK50)",
    author = "C. {Ralfs}",
    year = "2014",
    publisher = "GRIN Verlag",
    address = "München, Germany",
    url = "https://www.hausarbeiten.de/document/280431"
}