@book { DieEuropischeUnionvorneuenHerausforderungen,
    title = "Die Europäische Union vor neuen Herausforderungen",
    author = "Gerald G. {Sander} and Ivo {Maryska}",
    year = "2021",
    publisher = "Peter Lang Verlag",
    address = "Berlin, Germany",
    url = "https://www.peterlang.com/document/1097913"
}