@book { PreuenunterFriedrichWilhelmII17861797,
    title = "Preußen unter Friedrich Wilhelm II. (1786-1797)",
    author = "Wilhelm {Bringmann}",
    year = "2001",
    publisher = "Peter Lang Verlag",
    address = "Berlin, Germany",
    url = "https://www.peterlang.com/document/1091713"
}