An Attempt to Characterise the State of the Teutonic Knights in Prussia - Czaja, Roman; Nowak, Zenon Hubert (. The @Teutonic Order in Prussia and Livonia. - Torun : Towarzystwo Naukowe w Toruniu, 2015. - 422 Seiten. - Illustrationen. - ISBN 978-83-65127-11-2, 2015)