Zapadnye Slavi︠a︡ne i Kievskai︠a︡ Rusʹ  v X-XI vv /
Academy of Sciences of the Union of Soviet Socialist Republics (Moscow). - Institute of Slavonic Studies.
Koroli︠u︡k, V. D.
Tikhomirov, M. I.
Moskva,
1964.
[With a bibliography.]