@book { SteuerbefreiungenfrInlandsumstze4Nrn8bis28UStG,
    title = "Steuerbefreiungen für Inlandsumsätze (§ 4 Nrn. 8 bis 28 UStG)",
    author = "Philipp {Hoffsümmer}",
    year = "2021",
    publisher = "Peter Lang Verlag",
    address = "Berlin, Germany",
    url = "https://www.peterlang.com/document/1106977"
}