@book { KarteninterpretationL3326Celle,
    title = "Karteninterpretation L 3326 Celle",
    author = "Matthias {Schopp}",
    year = "2014",
    publisher = "GRIN Verlag",
    address = "München, Germany",
    url = "https://www.hausarbeiten.de/document/284861"
}