¹⁷  Elena Toncheva, ‘Музикално Тълкуване (екзегезис) на балкански мелодии в скитския "Болгарский Роспев’ [trans. Musical 'interpretation' (exegesis) of Balkan melodies in the Scythian ‘Bolgarsky Rospev’]’, (in Bulgarian), Българско Музикознание, 2 (1988), 40-60. See also: Elena Toncheva, ‘Die musikalische Bedeutung des Interpunktionszeichens „Punkt“ in dem sticherarischen Repertoire der Handschrift NB Athens Nr. 928 (XV. Jh.) [trans. The musical meaning of the punctuation sign ‘Full point’ in the sticheraric repertoire of manuscript NB Athens Nr. 928 (XV. c.)]’, (in German), Ed. by P. Petersen, Musikkulturgeschichte: Festschrift für Constantin Floros, (Breitkoph&Härtel - Wiesbaden, 1990), 461-478, p. 475-6.