Мольков Г. А. Мена еров в ранней древнерусской орфографии (на материале рукописи Поучений огласительных Кирилла Иерусалимского рубежа XI–XII вв.) // Slavia. 2022, roč. 91, seš. 2. S. 193–213.
In the Old Russian writings of the 11th–12th centuries there are found spelling systems in which the letters ъ and ь are frequently confused with one another. The use of jers in such systems reflects the facts of different periods in the development of Slavonic writing. This article considers the East Slavonic copy of the Homilies by Cyril of Jerusalem, which provides indicative material for describing the heterogeneous nature of the jers’ confusion. This orthographic feature is presented in the manuscript by thousands of examples in a large number of morphemes. The analysis of complete sampling of material on variation of the letters ъ and ь and comparison of the spelling of the Old Russian manuscript with the testimony of Old Slavonic manuscripts allows us to show that some of jers in non-etymological positions owe their appearance to the East Slavonic scribe. The highest frequency of confusion is reached in spelling groups with orthographically marked positions that were subject to recoding in the process of developing the original Old Russian spelling norm. The considered data suggest that the perception of South Slavonic spelling with a confusion of jers in Rus’ was not limited to simple copying, but could provoke the appearance of original spelling techniques.