@book { ParadigmWarsValidityandReliabilityinQualitativeResearch,
    title = "Paradigm Wars - Validity and Reliability in Qualitative Research",
    author = "Matthias {Baumgarten}",
    year = "2012",
    publisher = "GRIN Verlag",
    address = "München, Germany",
    doi = "10.3239/9783656113584",
    url = "https://www.hausarbeiten.de/document/187932"
}