@book { PreisundMarkendehnung,
    title = "Preis und Markendehnung",
    author = "Katia {Rumpf}",
    year = "2012",
    publisher = "Peter Lang Verlag",
    address = "Berlin, Germany",
    doi = "10.3726/978-3-653-01026-8",
    url = "https://www.peterlang.com/document/1045730"
}