@book { CivitasEuropaea,
    title = "Civitas Europaea",
    author = "Till {Bellinghausen}",
    year = "2012",
    publisher = "Peter Lang Verlag",
    address = "Berlin, Germany",
    doi = "10.3726/978-3-653-01771-7",
    url = "https://www.peterlang.com/document/1046822"
}