Козовик, І. “Relations Between the Galicia-Volyn State and the Roman Apostolic See in the Light of Archival Documents of the Vatican”. Good Parson: Scientific Bulletin of Ivano-Frankivsk Academy of John Chrysostom. Theology. Philosophy. History, no. 1, Dec. 2007, pp. 216-27, http://journal.ifaiz.edu.ua/index.php/gp/article/view/269.