@book { FriesischeHndlerundderfrhmittelalterlicheHandelamOberrhein,
    title = "Friesische Händler und der frühmittelalterliche Handel am Oberrhein",
    author = "Jens Boye {Volquartz}",
    year = "2017",
    publisher = "Peter Lang Verlag",
    address = "Berlin, Germany",
    doi = "10.3726/b11186",
    url = "https://www.peterlang.com/document/1049665"
}