His threatise Book of Joys .
In 1920 - 1924 he was a chairman of the Leningrad section of the Writers ' Union and for a while headed the Leningrad School of Choreography .
chairman 's threatise Book of Joys .
In 1920 - 1924 he was a chairman of the Leningrad section of the Writers ' Union and for a while headed the Leningrad School of Choreography .