@book { LudwigBechsteininBriefenanZeitgenossen,
    title = "Ludwig Bechstein in Briefen an Zeitgenossen",
    author = "Heinrich {Weigel}",
    year = "2021",
    publisher = "Peter Lang Verlag",
    address = "Berlin, Germany",
    url = "https://www.peterlang.com/document/1100914"
}