@book { KreativeFotoAufgabenKinderFamilie,
    title = "Kreative Foto-Aufgaben: Kinder & Familie",
    author = "Tom {Gufler}",
    year = "2019",
    publisher = "humboldt",
    address = "Hannover, Deutschland",
    url = "https://schluetersche.openpublishing.com/document/500433"
}