@book { VarianzimRussischen,
    title = "Varianz im Russischen",
    author = "Vladislava {Warditz}",
    year = "2019",
    publisher = "Peter Lang Verlag",
    address = "Berlin, Germany",
    doi = "10.3726/b14332",
    url = "https://www.peterlang.com/document/1055633"
}