Parallels from the pages of the Esztergom Missale Notatum and Graduale Romanum
Gregorian song - the text of which was prescribed by liturgy - sung to the tune of another song. Parallels from the pages of the Esztergom Missale Notatum and Graduale Romanum. Dobszay László: Magyar zenetörténet.
Gondolat, Budapest, 1984, page 51.