@book { UnterrichtseinheitDieUhrhat24Stunden,
    title = "Unterrichtseinheit: Die Uhr hat 24 Stunden",
    author = "Myriam {Dörr}",
    year = "2007",
    publisher = "GRIN Verlag",
    address = "München, Germany",
    doi = "10.3239/9783638631785",
    url = "https://www.hausarbeiten.de/document/71424"
}