@book { VingtansdUnificationallemande,
    title = "Vingt ans d’Unification allemande",
    author = "Bernd {Zielinski} and Brigitte {Krulic}",
    year = "2021",
    publisher = "Peter Lang Verlag",
    address = "Lausanne, Switzerland",
    url = "https://www.peterlang.com/document/1136004"
}