Many foreign authors have been interested in medieval Armenian spiritual music and especially in medieval notation or neumes –khaz in Armenian.

The first investigation among them was J. J. Schröder’s Thesaurus Linguae Armeniacae, antiqua et hodierna (Amstelodami, 1711). He represents a list of Armenian khazes and eight modes of church singing in old European notation

with Armenian texts.

The second author was H. Peterman, who, in his book Über die Musik der Armenier (Band V, Leipzig, 1851), investigated eight modes of Armenian spiritual music using also the previous author’s writings.

An abbot of the Armenian Mekhitarist Congregation of Venice, Father Ignatios Kyureghian, in his large series of articles entitled Investigation of Sharakan Khazes, represents in Armenian translation some passages from the book of a French researcher, A.-G. Villoteau – Description de l’Egypte (Tome XIV, Paris, 1809-1829, second edition, known as the Panckoucke edition), as well as from the book on Latin neumes by a Benedictine monk, Padre D. G. Pothier – La Mélodie Grégorienne(Tournai, Roma, 1875, cited inBazmavep, 1900, 1903, 1904).

The founder of the weekly Revue Musicale in Paris, a Belgian specialist of ethno-musicology, F. J. Fetis, in his book Histoire Générale de la Musique (Tome IV, Paris, 1874), also represented medieval Armenian musical notation and modes of spiritual music.

Օne of the founders of the International Musicological Society, a German specialist of neumes, O. Fleischer, investigated medieval Armenian musical notation, especially signs of pronunciation, in 1899.

The French armenologist and one of the founders and editors of the wellknown Revue des Études Arméniennes F. Macler also wrote a brief book on Armenian music – La musique en Arménie (Paris, 1917).

In the journal Bazmavep there is the translation ofanother article on Armenian music by a German musicologist,a specialist of medieval church music P. Wagner – The Russian and Armenian Neumes (Bazmavep, 1913, pp. 6-10, 71-76), in which the author writes about Armenian neumes as one of the oldest forms of musical notation in the world.