@book { KarlPoppersResponseto1938,
    title = "Karl Popper’s Response to 1938",
    author = "Peter {Markl} and Erich {Kadlec}",
    year = "2021",
    publisher = "Peter Lang Verlag",
    address = "Berlin, Germany",
    url = "https://www.peterlang.com/document/1105448"
}