@book { HerbertGruhlUnterdenKarawanenderBlinden,
    title = "Herbert Gruhl – Unter den Karawanen der Blinden",
    author = "Volker {Kempf}",
    year = "2021",
    publisher = "Peter Lang Verlag",
    address = "Berlin, Germany",
    url = "https://www.peterlang.com/document/1100136"
}