@book { PolitischesSystemdesKleinststaatesLiechtenstein,
    title = "Politisches System des Kleinststaates Liechtenstein",
    author = "Stefan {Hansen}",
    year = "2003",
    publisher = "GRIN Verlag",
    address = "München, Germany",
    doi = "10.3239/9783638195713",
    url = "https://www.hausarbeiten.de/document/14075"
}