@book { InmehrerenSprachenstudieren,
    title = "In mehreren Sprachen studieren",
    author = "Rahel {Stoike-Sy}",
    year = "2017",
    publisher = "Peter Lang Verlag",
    address = "Berlin, Germany",
    doi = "10.3726/978-3-653-06787-3",
    url = "https://www.peterlang.com/document/1050499"
}