Original sentence: Bialecki (1992) and Barber (2004) note that this included land up to the island of Rugia (according to Bialecki), or up to the Oder line in 1129 (according to Barber).In a campaign in the winter of 1121–1122, Bolesław III Wrymouth, the Duke of Poland, regained control of the region and the stronghold of Szczecin.Piskorski (1999), Buchholz (1999), Buske (1997), and Inachim (2008), state that the area had not subjugated before by Boleslaw, that the Szczecin campaign of Boleslaw had already crossed the Oder line , and that the Principality of Rugia, despite the subsequent westward expansion of Wartislaw I, Duke of Pomerania, was independent until the Danish capture in 1168
Edited sentence: Bialecki (1992) and Barber (2004) in a book about medieval Europe describe this as a regain of territory - up to the island of Rugia (according to Bialecki), or up to the Oder line in 1129 (according to Barber).In a campaign in the winter of 1121–1122, Bolesław III Wrymouth, the Duke of Poland, gained control of the stronghold.Knoll and Schaer (2003) and the books about Pomeranian history of historians Piskorski (1999), Buchholz (1999), Buske (1997), and Inachim (2008), contradict these informations saying the area was not subjugated before, that the Stettin campaign of Boleslaw had already crossed the Oder line, and that the Principality of Rugia, despite the subsequent westward expansion of Wartislaw I, Duke of Pomerania, was independent until the Danish capture in 1168