Inscription: On rev., in Greek: sabao phren Iao, in three lines
Bonner, Campbell. 1949. "An Amulet of the Ophite Gnostics." Commemorative studies in honor of Theodore Leslie Shear, Hesperia Supplement: p. 45 n. 10.
Bonner, Campbell. 1950. Studies in Magical Amulets, Chiefly Graeco-Egyptian, University of Michigan Studies, Humanistic Series, Vol. 49. no. 231, p. 292, pl. 11, Ann Arbor: University of Michigan Press.