@book { ParteienfamilieohneZusammenhalt,
    title = "Parteienfamilie ohne Zusammenhalt?",
    author = "Bernd {Sondermann}",
    year = "2021",
    publisher = "Peter Lang Verlag",
    address = "Berlin, Germany",
    url = "https://www.peterlang.com/document/1101609"
}