@book { StadtentwicklunginaltindustriellenRegionen,
    title = "Stadtentwicklung in altindustriellen Regionen",
    author = "Christian {Feldkamp}",
    year = "2008",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    url = "https://m.diplom.de/document/225493"
}