@book { NurdasDenkendaswirlebenhateinenWert,
    title = "Nur das Denken, das wir leben, hat einen Wert",
    author = "Ursula {Kliewer} and Heinz-Jürgen {Kliewer}",
    year = "2021",
    publisher = "Peter Lang Verlag",
    address = "Berlin, Germany",
    url = "https://www.peterlang.com/document/1106985"
}