@book { ReformnotwendigkeitenundReformmglichkeitendes4IIIEStG,
    title = "Reformnotwendigkeiten und Reformmöglichkeiten des § 4 III EStG",
    author = "Björn {Büssen}",
    year = "2021",
    publisher = "Peter Lang Verlag",
    address = "Berlin, Germany",
    url = "https://www.peterlang.com/document/1106747"
}