@book { EUGrundrechteundUmsatzsteuer, title = "EU-Grundrechte und Umsatzsteuer", author = "Markus {Müller}", year = "2021", publisher = "Peter Lang Verlag", address = "Berlin, Germany", doi = "10.3726/b18610", url = "https://www.peterlang.com/document/1063424" }