His extensive bibliography includes over 400 titles. Some of his most influential books available in multiple languages include:
: He has critically analyzed the origins of the Slavic population in the Eastern Alps, challenging older theories of direct continuity from medieval tribal formations. Peter Е tih
His work typically focuses on the Alpine-Adriatic region between the end of Antiquity and the 15th century. Key areas of his research include: His extensive bibliography includes over 400 titles