@book { WieKinderrechnenlernenoderauchnicht,
    title = "Wie Kinder rechnen lernen – oder auch nicht",
    author = "Michael {Gaidoschik}",
    year = "2012",
    publisher = "Peter Lang Verlag",
    address = "Berlin, Germany",
    doi = "10.3726/978-3-653-01218-7",
    url = "https://www.peterlang.com/document/1054199"
}