@book { ThePolishMiddleClass,
    title = "The Polish Middle Class",
    author = "Henryk {Domański}",
    year = "2015",
    publisher = "Peter Lang Verlag",
    address = "Berlin, Germany",
    doi = "10.3726/978-3-653-04349-5",
    url = "https://www.peterlang.com/document/1067582"
}