@book { TheGDRToday,
    title = "The GDR Today",
    author = "Stephan {Ehrig} and Marcel {Thomas} and David {Zell}",
    year = "2018",
    publisher = "Peter Lang Verlag",
    address = "Oxford, United Kingdom",
    url = "https://www.peterlang.com/document/1054856"
}