The wars of the Russians and Greeks in the
ixth, xth, and xith centuries, are related in the Byzantine
annals, especially those of Zonaras and Cedrenus; and all
their testimonies are collected in the Russica of Stritter,
tom. ii. pars ii. p. 939 - 1044.
The History Of The Decline And
Fall Of The Roman Empire
—Fall In The East