Hypatian Codex

The Hypatian Codex, also known as Hypatian Letopis or Ipatiev Letopis, is a compendium of three Rus' chronicles: the Primary Chronicle, Kievan Chronicle and Galician-Volhynian Chronicle. It is the most important source of historical data about Kievan Rus'. The language of this work is Old Church Slavonic with many East Slavisms.