Vol. 15 also called American series 1. Editors: 1924- P. Graindor, H. Grégoire. V. 25-27, 1955-1957, issued combined. Organ of the Centre national de recherches byzantines, 1958-62; of the Société belge d'Etudes byzantines, 1963- Vol. 15-17 pub. by the Byzantine Institute and have subtitle: International journal of Byzantine studies (American series, I-III).