@book { EinleitunginphilosophischeVorlesungen,
    title = "Einleitung in philosophische Vorlesungen",
    author = "Henrich {Steffens}",
    year = "2013",
    publisher = "Peter Lang Verlag",
    address = "Berlin, Germany",
    doi = "10.3726/978-3-653-02058-8",
    url = "https://www.peterlang.com/document/1047370"
}