(in Russian) Nikolay Petrovsky. Who stole the cross of St. Euphrosyne // Echo Planety, No. 11, 2000 [1]Archived February 28, 2009, at the Wayback Machine
(in Russian) Nikolay Petrovsky. Who stole the cross of St. Euphrosyne // Echo Planety, No. 11, 2000 [1]Archived February 28, 2009, at the Wayback Machine