@book { GiuseppeVerdiinWien,
    title = "Giuseppe Verdi in Wien",
    author = "Günther {Berger}",
    year = "2013",
    publisher = "Peter Lang Verlag",
    address = "Berlin, Germany",
    doi = "10.3726/978-3-653-02862-1",
    url = "https://www.peterlang.com/document/1046630"
}