@book { PolnischeIdentitt,
    title = "Polnische Identität",
    author = "Peter {Grabowitz}",
    year = "2012",
    publisher = "GRIN Verlag",
    address = "München, Germany",
    doi = "10.3239/9783656182221",
    url = "https://www.hausarbeiten.de/document/192954"
}