Lyudmila Doncheva-Petkova is Professor, Doctor of Historical Sciences at the National Archaeological Institute with Museum, Sofia. She is one of the best scholars of early medieval Bulgarian archaeology and is among the scientist of international renown. For more than 35 years she has been exploring the area on the west wall of the first Bulgarian capital Pliska, where besides the fortress facilities, she revealed complexes of buildings, glass furnaces, furnaces for melting iron, various household items, many ceramics. In Pliska she also found a remarkable triple cross - two golden and a wooden one placed in each other. This monument now proudly occupies a place among the most famous works of Byzantine art. In 1997-2001, L. Doncheva-Petkova directed a Bulgarian-German expedition in Pliska that explored the outer city near Hazar River gully. In recent years she has revealed a new complex of buildings near the western wall. For years, she has been examining early medieval monuments in Dobrogea - early Byzantine fortress town from the First Bulgarian Kingdom and two Pechenegs necropolises near the village of Odurtsi, Dobrich Region; she led and participated in the study of the largest bi-ritual necropolis in Topola, Kavarna; she revealed the earliest proto necropolis near the town of Balchik. She participated in excavations of the famous Desnobrezhno Tsimlyansko gradishte in Russia. Lyudmila Doncheva-Petkova is the author of more than 150 scientific papers, including 8 monographs. Her new book, "Medieval-enkolpion crosses from Bulgaria" is the result of more than 30 years of research and study of enkolpia. She has studied a rich and varied material, and its dating is mainly based on monuments found during excavation or analogies with the monuments of Byzantine art."