@book { ObstjoghurtherstellenmitKindern,
    title = "Obstjoghurt herstellen mit Kindern",
    author = "Olivia {Bühlinger}",
    year = "2013",
    publisher = "GRIN Verlag",
    address = "München, Germany",
    doi = "10.3239/9783656573807",
    url = "https://www.hausarbeiten.de/document/266642"
}