@book { ITDienstleistungenfrKommunen,
    title = "IT-Dienstleistungen für Kommunen",
    author = "Torsten {Arnold}",
    year = "2001",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    doi = "10.3239/9783832440022",
    url = "https://m.diplom.de/document/219637"
}