@book { DerBriefwechselvonJakobBurckhardtundPaulHeyse,
    title = "Der Briefwechsel von Jakob Burckhardt und Paul Heyse",
    author = "Jakob {Burckhardt} and Paul {Heye}",
    year = "2021",
    publisher = "Peter Lang Verlag",
    address = "Lausanne, Switzerland",
    url = "https://www.peterlang.com/document/1069295"
}