@book { AuenpolitikvonStdten,
    title = "Außenpolitik von Städten",
    subtitle = "Glasgow-Köln-Wien",
    author = "Susanne {Fohr}",
    year = "2001",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    doi = "10.3239/9783832431709",
    url = "https://m.diplom.de/document/218866"
}