... chronicle narratives about the campaign of Russian princes to Tsargrad

Istrin, Vasily Mikhailovich (1865-1937).... chronicle narratives about the campaigns of Russian princes on Tsargrad / V.M.Eastrin.- Petrograd: Type.Imp.Acad.Sciences, 1917. - [2], 22 s.;25. -OTT.From "Izv. Depth Rus. Jaz. and the literature imp. Acade. Sciences."T. 21, (1916), KN.2..Electronic Source: PB