Printed Blank Forms are poorly studied historical sources. They were published in almost every printing house, often in large editions; however, due to the specifics of the purpose, they were poorly preserved. Many of the printed editions have not reached our days. You can learn about their existence from archival documents. A number of editions are known in a single copy. The Research Department of Rare Books (Book Museum) of the Russian State Library has two Printed Blank Forms. These are the Certificates of Ordination from the Bishop of Pinsk and Turov, George Bulgak. These are the only known copies of the editions. They were issued to priest Vasily Shemetil on July 15, 1759 in Pinsk and stamped with the Episcopal seal. They came from the Vilnius Public Library. Due to the small number of complex studies of such sources, the article provides the detailed description of them, reveals the content at the level of the edition (printed blank form) and the copy (handwritten text); for the first time there is undertaken publication of the texts of the certificates. Moreover, the authors consider the actual problems of the bibliographic description of these publications: different bibliographers (F.N. Dobryansky, A.I. Milovidov, G.Y. Golenchenko, Y.A. Labyntsev) described and attributed these editions differently (Mogilev and Suprasl were mentioned as the place of publication). Being unique sources, they attracted attention of bibliographers, but were not used at all by historians and other researchers of book culture. The authors come to the conclusion that the attribution of the publication of letters in the printing house of the Annunciation Monastery in Suprasl, proposed by Y.A. Labyntsev, looks the most convincing today. The study emphasizes the importance of the considered documents that are the only known examples of printed Greek Catholic Certificates of Ordination of the 18th century. Since the life and activity of Georgy Bulgak himself, who became the Archimandrite of the Annunciation Monastery in Suprasl, remains practically unexplored in Russian historiography, the article presents his biography, focuses on this period of his activity and his great contribution to the development of book publishing in the monastery printing house, which printed books in Slavic, Polish and Latin languages.