@book { QualittsrelevanteServiceleistungen,
    title = "Qualitätsrelevante Serviceleistungen",
    author = "Volker {Kißling}",
    year = "1997",
    publisher = "Diplom.de",
    address = "Hamburg, Deutschland",
    doi = "10.3239/9783832402389",
    url = "https://m.diplom.de/document/216184"
}