↑ Under 981, the Primary Chronicle reports on Volodymyr's campaign against the Poles, which resulted in the capture of "their towns" Peremyshl and Cherven. As the chronicler notes, they remained under Rus' control until his own time. In: S. Plokhy. "The origins of the Slavic nations: premodern identities in Russia, Ukraine, Belarus". Cambridge University Press, 2006. p. 57.
↑ A. Buko. "The archaeology of early medieval Poland". Brill. 2008. pp. 307-308
↑ Przemysław Wiszewski. Domus Bolezlai: Values and Social Identity in Dynastic Traditions of Medieval Poland (c. 966-1138). BRILL. 2010. p. 445.
