@book { DieEuropischePolitischeGemeinschaftEPG1953unddieEuropischeUnionEU2001,
    title = "Die Europäische Politische Gemeinschaft (EPG) 1953 und die Europäische Union (EU) 2001",
    author = "Christof {Berthold}",
    year = "2021",
    publisher = "Peter Lang Verlag",
    address = "Berlin, Germany",
    url = "https://www.peterlang.com/document/1095782"
}