@book { QualittsentwicklunganWaldorfschulen,
    title = "Qualitätsentwicklung an Waldorfschulen",
    author = "Richard {Landl} and Jürgen {Peters} and Alexander {Röhler}",
    year = "2016",
    publisher = "Peter Lang Verlag",
    address = "Berlin, Germany",
    doi = "10.3726/978-3-653-06495-7",
    url = "https://www.peterlang.com/document/1050060"
}