LINGUITIC PRINCIPLES IN ZNAMENNY NOTATION (ON THE MATERIAL OF THEORETIC MUSICAL TREATISE "KLUCH RAZUMENIYA")
The article shows that the means of the znamenny chant notation had formed a compound sign system by the end of the 17 <sup>th</sup> century. According to the functions performed by them the author proposes to differentiate them into basic and optional. Similarity of the znamenny notation to verbal writing is established.