@book { DieAneignungfremderSprachen,
    title = "Die Aneignung fremder Sprachen",
    author = "Gerhard {Bach} and Britta {Viebrock}",
    year = "2021",
    publisher = "Peter Lang Verlag",
    address = "Berlin, Germany",
    url = "https://www.peterlang.com/document/1094048"
}