@book { DieAnfngevonGeburtenbeschrnkung,
    title = "Die Anfänge von Geburtenbeschränkung",
    author = "Ulrich {Pfister}",
    year = "2021",
    publisher = "Peter Lang Verlag",
    address = "Lausanne, Switzerland",
    url = "https://www.peterlang.com/document/1070874"
}