Evans, Helen C., and William D. Wixom, ed. The Glory of Byzantium: Art and Culture of the Middle Byzantine Era, A.D. 843-1261. New York: The Metropolitan Museum of Art, 1997. no. 3, p. 38.
Evans, Helen C., Melanie Holcomb, and Robert Hallman. "The Arts of Byzantium." The Metropolitan Museum of Art Bulletin, n.s., 58, no. 4 (Spring 2001). p. 43.