@book { ITStrategie,
    title = "IT-Strategie",
    subtitle = "Konzepte und Implementierungsstrategien im Service-Level-Management",
    author = "Christoph {Seidel}",
    year = "2006",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    doi = "10.3239/9783832492199",
    url = "https://m.diplom.de/document/224342"
}