Чугуй, Т. “Pressing Historiography Questions of Halych-Volyn Prince Roman Mstyslavovych’s Life”. V. N. Karazin Kharkiv National University Bulletin ‘History of Ukraine. Ukrainian Studies: Historical and Philosophical Sciences’, Vol. 22, Dec. 2016, pp. 6-23, https://periodicals.karazin.ua/uahistory/article/view/7249.