Original sentence: Chernorizets Hrabar is the credited author of only one literary work, "On the Letters" (, O pismenĭhŭ, ), a popular medieval treatise written in Old Church Slavonic.The authorship of his work and his identity have been a matter of scholarly debate
Edited sentence: Chernorizets Hrabar is the credited author of only one literary work, "On the Letters" (, O pismenĭhŭ, ), one of the most admired and popular works of literature written in Old Church Slavonic.No biographical information is available about him