@book { QualittsunterschiedeinderPflege,
    title = "Qualitätsunterschiede in der Pflege",
    author = "Philipp {Barthel}",
    year = "2008",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    doi = "10.3239/9783836614641",
    url = "https://m.diplom.de/document/225880"
}