@book { TheodorWolffundderErsteWeltkrieg19141918,
    title = "Theodor Wolff und der Erste Weltkrieg 1914-1918",
    author = "Birgit {Zimmer-Wagner}",
    year = "2021",
    publisher = "Peter Lang Verlag",
    address = "Berlin, Germany",
    url = "https://www.peterlang.com/document/1098975"
}