Question: The Association for Contemporary Music's leading members include what Russian composer of the early Soviet era, best known for his early futurist piano sonatas, orchestral episodes, and vocal music?
Sentence (from "Alexander Mosolov"): Alexander Vasilyevich Mosolov (Russian: Алекса́ндр Васи́льевич Мосо́лов , "Aleksandr Vasil'evič Mosolov" ; 11 August [O.S. 29 July] 1900  – 11 July 1973) was a Russian composer of the early Soviet era, known best for his early futurist piano sonatas, orchestral episodes, and vocal music.
Relevant evidence: Yes