@book { NietzschesZarathustraalsmoderneTragdie,
    title = "Nietzsches «Zarathustra» als moderne Tragödie",
    author = "Winfried {Happ}",
    year = "1985",
    publisher = "Peter Lang Verlag",
    address = "Berlin, Germany",
    url = "https://www.peterlang.com/document/1073302"
}