@book { OutsourcingpersonalwirtschaftlicherFunktionen,
    title = "Outsourcing personalwirtschaftlicher Funktionen",
    author = "Stephan {Kaiser}",
    year = "2001",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    doi = "10.3239/9783832436612",
    url = "https://m.diplom.de/document/219311"
}