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Krez (Udmurt and Russian: крезь) is an Udmurtstring instrument (chordophone) similar to the Russian gusli. The mythical origin of krez is detailed in the Udmurt national epic, Dokjavyl. Krez was used to accompany some shamanic ritual dances, and large krez (быдӟым крезь) was used for music during the holiday of Bulda.
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Mare Kõiva; Kai Vassiljeva; Eesti Keele Instituut (Eesti Teaduste Akadeemia); Fr. R. Kreutzwaldi nimeline Kirjandusmuuseum (1995). Folk belief today. Estonian Academy of Sciences, Institute of the Estonian Language & Estonian Museum of Literature. p. 29. ISBN978-9985-851-11-1. Retrieved 17 June 2012.