@book { DieOperKrlRogervonKarolSzymanowski,
    title = "Die Oper «Król Roger» von Karol Szymanowski",
    author = "Jadwiga {Makosz}",
    year = "2021",
    publisher = "Peter Lang Verlag",
    address = "Berlin, Germany",
    url = "https://www.peterlang.com/document/1135957"
}