Analysis of information sources in references of the Wikipedia article "Cyrillic script" in English language version.
The Psalter and the Book of Prophets were adapted or "modernized" with special regard to their use in Bulgarian churches and it was in this school that the Glagolitic script was replaced by the so-called Cyrillic writing, which was more akin to the Greek uncial, simplified matters considerably and is still used by the Orthodox Slavs.
Cyrillic was apparently adopted by the followers of Cyril and Methodius in Bulgaria (where they had retired at the invitation of the Czar of the Bulgars as a more favorable field for their activities, after encountering opposition from western oriented missionaries in Moravia).
Another inscription found by Popkonstantinov during the survey of the monastery speaks of the time of its creation. It consists of nine lines and has come down to us much damaged. 59 letters are saved. The first three lines are readable. What is preserved of him reads: "In the year 921, in the month of October, the servant of God Anton died..."
