@book { QualitativeundquantitativeForschungsmethodenimVergleich,
    title = "Qualitative und quantitative Forschungsmethoden im Vergleich",
    author = "Serafina {Morrin}",
    year = "2014",
    publisher = "GRIN Verlag",
    address = "München, Germany",
    url = "https://www.hausarbeiten.de/document/283585"
}