@book { DieEigenkapitalberlassunginderUmsatzsteuer,
    title = "Die Eigenkapitalüberlassung in der Umsatzsteuer ",
    author = "Johannes {Theobald}",
    year = "2020",
    publisher = "Peter Lang Verlag",
    address = "Berlin, Germany",
    doi = "10.3726/b16654",
    url = "https://www.peterlang.com/document/1058767"
}