@book { StaatenlexikonEuropa,
    title = "Staatenlexikon Europa",
    author = "Andreas {Dittmann} and Wolfgang {Gieler}",
    year = "2019",
    publisher = "Peter Lang Verlag",
    address = "Berlin, Germany",
    doi = "10.3726/b15960",
    url = "https://www.peterlang.com/document/1110819"
}