@book { WalthervonderVogelweideDasgradualistischeIdealindendingen,
    title = "Walther von der Vogelweide: Das gradualistische Ideal «in den dingen»",
    author = "Rainer {Nübel}",
    year = "2018",
    publisher = "Peter Lang Verlag",
    address = "Berlin, Germany",
    doi = "10.3726/b14437",
    url = "https://www.peterlang.com/document/1056940"
}