* [http://www.uni-kiel.de/ufg/images/stories/userpic/umueller/mueller_urbanization_2010.pdf Ulrich Müller: "Trading centres – Hanseatic towns on the southern Baltic Coast: Structural continuity or a new start?" (Babette Ludowici, Hauke Jöns, Sunhild Kleingärtner, Jonathan Scheschkewitz und Matthias Hardt (udg.): Trade and Communication Networks of the First Millennium AD in the northern part of Central Europe: Central Places, Beach Markets, Landing Places and Trading Centres"; ''Neue Studien zur Sachsenforschung Band 1''; ISBN 978-3-8062-2412-2)] (engelsk)
