Bariolage is a bow-technique on string instruments that involves rapid alternation of strings with the bow. It is a French word for “multi-colored” or “odd mixture of colours”, from the verb barioler, “to streak with several colors”.
In pieces such as Ascetic Discourse, Unceasing Prayers and PSALM XIII Zivkovic uses that technique extensively. The symbol that represents bariolage is Br. for a single note and Br.~ for tied notes or continuous bariolages of the same pitch (theoretically speaking it has the same usage as it would be with tr~ in trill.)
Legato bariolage is in the fact normal legato tremolo. However, its main distinction is in the visual discrimination between main melody and tremolo/trill tones.
The speed can be controlled by musicians. In general, slow melodic lines can be played with slow bariolage oscillations, and quick changes in the main melody require a faster bariolage. In the orchestra, the speed of bariolage is not important because of the great number of players who execute the same bariolage/melody.
Combining with unison
In Ascetic Discourse the bariolage playing within unison is used for the first time.  It means that one single performer has to play on two different strings the same note (same pitch) and play bariolage between them. In the following example it is worth noting that not only playing of the same pitch but also singing of the same pitch is involved in the musical structure.
The effect is absolutely astonishing, making a choir-like sound out of instruments, particularly because the perfect unison playing on string instruments is very hard, thus the micro-tonal oscillations make it choir-like.
The bariolage playing can be very tiresome if it is executed improperly. The basic mistake is found in playing of bariolage with the whole hand. Therefore, the bariolage must be executed only with the palm of hand (right hand).
Notes 1. It is not known that this technique is used by any other composer before.