@book { GeschichteEineTheorie,
    title = "Geschichte: Eine Theorie",
    author = "Karl Heinz {Metz}",
    year = "2015",
    publisher = "Peter Lang Verlag",
    address = "Berlin, Germany",
    doi = "10.3726/978-3-653-05775-1",
    url = "https://www.peterlang.com/document/1049527"
}