@book { SustainableDevelopmentalsParadigmamodernerPdologiebeiEllenKey,
    title = "Sustainable Development als Paradigma moderner Pädologie bei Ellen Key",
    author = "Margrit {Hansen}",
    year = "2021",
    publisher = "Peter Lang Verlag",
    address = "Berlin, Germany",
    url = "https://www.peterlang.com/document/1096000"
}