A North German Prince on a Pilgrimage in Arms : Political Implications of the Livonian Crusade of Albert I, Duke of Saxony - Kaljusaar, Kristjan (. The @expansion of the faith. - Turnhout : Brepols, [2022]. - 350 Seiten. - Illustrationen, Karten. - ISBN 978-2-503-58880-3, 2022)