@book { EinfhrungeinesQualittsmanagementSystems,
    title = "Einführung eines Qualitätsmanagement-Systems",
    author = "Ernst {von Petersdorff}",
    year = "2002",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    doi = "10.3239/9783832449025",
    url = "https://m.diplom.de/document/220471"
}