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Referenced as figure 183 in The military technology of classical Islam by D Nicolle
183. Fresco from Faras Cathedral, St. Mercurius, late 8th century AD, Nubian, Polish National Museum no. 149672MN, Warsaw (Michal).
K. Michalowski, Faras, Die Kathedrale aus dem Wüstensand, (Zurich 1967).