V. Chkhaidze, "Byzantine lead seals addressed to Matarcha from the sixth to the twelfth century", in H. Ivakin (ed.), Byzantine and Rus’ seals: proceedings of the international colloquium on Rus’-Byzantine sigillography (Kyiv, Ukraine, 13-16 September 2013), Kiev, 2015, p. 61-70.
| p. 63 |