@book { OutsourcingimSupplyChainManagement,
    title = "Outsourcing im Supply Chain Management",
    author = "Oliver {Eitelwein}",
    year = "2004",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    doi = "10.3239/9783832475833",
    url = "https://m.diplom.de/document/222860"
}