@book { Kopplungsangebote,
    title = "Kopplungsangebote",
    author = "Daniel {Travers}",
    year = "2015",
    publisher = "Peter Lang Verlag",
    address = "Berlin, Germany",
    doi = "10.3726/978-3-653-05276-3",
    url = "https://www.peterlang.com/document/1049264"
}