The beginnings of printing after Gutenberg's invention and the printing of the first books of the so called incunabula represent a huge cultural, technological and even informational progress in the life and development of those nations wko were lucky enough to print incunabula. The speed of information transfer was rapidly increased by the invention of printing, because books began to be printed in circulations of several hundred copies, which was unthinkable with the production of manuscript books before that. As the question of the location of the first printing house in Croatia, and consequently the location of printing our first book, is still open, the main direction of this doctorate will be a systematic and comprehensive information-historical analysis of all current theses on the location of our first printing house. Then, through archival research, the application of information methods and cartographic and historical analysis, some new insights will be offered around Kosinj as a possible locality of our first printing house. The goal is ultimately to get the first paper in the Croatian language, which will address the entire issue of the beginnings of printing our incunabula, as well as the possible locations of our first printing house. Through new findings, the work will possibly strengthen Kosinj on the map of the world's first printing houses, published in 1962 at the Gutenberg Museum in Mainz. The Croatian people, who printed the first non-Latin missal in the Europe and the only one to print incunabula in three languages and two scripts, deserve for the first time to receive an objective and complete historiographical treatment of this culturally extremely important topic.