The oldest Cyrillic manuscript preserved in Bulgaria exhibited at the National Library

The Enina Apostle is an Old Bulgarian manuscript dating to the 10th-11th century and is the oldest Cyrillic manuscript preserved on the territory of Bulgaria. It is written in ancient Cyrillic - in a sloping uncial and contains apostolic readings from the time of the 35th Sunday after Pentecost to the vespers of Great Saturday and from September 1 to October 3, the day of St. Dionysius the Areopagite.

In addition to this early type of Cyrillic script, several Glagolitic initials have been preserved in the text of the manuscript, mainly with the letter "B", which, together with the other linguistic, textological and ornamental features of the artefact, indicate its connection with the earliest Glagolitic tradition.

The Argirov triod manuscript dates back to the early 13th century. The fragment consisting of 58 leaves inscribed on parchment contains parts of a liturgical book. The manuscript is the work of a scribe who probably copied the text from an older Glagolitic manuscript or a manuscript that had preserved the connection with the Glagolitic tradition.

Another feature of the artefact is the presence of musical signs from the Old Byzantine neumes system, although applied indiscriminately.