@book { FehlendeDateninAdditivenModellen,
    title = "Fehlende Daten in Additiven Modellen",
    author = "Thomas {Nittner}",
    year = "2021",
    publisher = "Peter Lang Verlag",
    address = "Berlin, Germany",
    url = "https://www.peterlang.com/document/1096125"
}