@book { VertrauensbeziehungeninUnternehmen,
    title = "Vertrauensbeziehungen in Unternehmen",
    author = "Peter {Kels}",
    year = "2002",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    url = "https://m.diplom.de/document/221531"
}