@book { KreativbastelnmitNaturmaterialien,
    title = "Kreativ basteln mit Naturmaterialien",
    author = "Marie-Odette {Sommer} and Günter {Bauer}",
    year = "2010",
    publisher = "humboldt",
    address = "Hannover, Deutschland",
    url = "https://schluetersche.openpublishing.com/document/403379"
}