@book { SeinSinnundWerte,
    title = "Sein, Sinn und Werte",
    author = "Yvanka B. {Raynova}",
    year = "2017",
    publisher = "Peter Lang Verlag",
    address = "Berlin, Germany",
    doi = "10.3726/b11868",
    url = "https://www.peterlang.com/document/1048165"
}