The Tropologion is considered the earliest known extant chant book from the early Christian world which was in use until the twelfth century. The study of this book is still in its infancy. It has generally been believed that the book has survived in Georgian translation under the name 'ladgari' but similar books have been discovered in Greek, Syriac and Armenian. All the copies clearly show that the spread and the use of the book were much greater than we had previously assumed and the Georgian ladgari is only one of its many versions.

Svetlana Kujumdzieva is Professor of Medieval Music at the Bulgarian Academy of Sciences and also at the National Musical Academy and Theological Faculty of the Sofia State University "St. Clement of Ohrid". She has specialized in Byzantine and Slavic music at the Institute of Musicology, University of Hamburg (1986) and at the Dumbarton Oaks Center for Byzantine Studies, University of Harvard (1994). She has been an associate member of the John W. Kluge International Center, Library of Congress, Washington DC; of the Resource Center for Medieval Slavic Studies, Ohio State University, Columbus, OH; of St. John College, Oxford; and of St. Louis University in St. Louis, MO. She has published eight books and over 150 articles.

1. The Hymnographic Book of Tropologion - Perspectives of the Study 2. The Early Sources 3. The Georgian Iadgari 4. The Syriac Tropligin 5. The Greek Tropologion 6. Was There an Old Slavic Tropologion? 7. Relics of Tropologion 8. The Tropologion in Its Historical Transmission Bibliography