A letter written by Edgard Varèse to Léon Theremin in 1941.
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Edgard Varèse
Edgar Varèse (1883 – 1965) was an innovative French-born composer who spent the greater part of his career in the United States. Under Varèse's specifications, Lèon Theremin built two fingerboard theremins that were to be used in Ecuatorial, a composition that Varèse wrote in the early 30's.