Question: The Philip Glass Ensemble is a musical group founded by composer Philip Glass in 1968, his first opera is which opera in four acts (framed and connected by five "knee plays" or intermezzos), composed by Philip Glass, and directed by theatrical producer Robert Wilson?
Sentence (from "Seymour Barab"): Seymour Barab (January 9, 1921 – died June 28, 2014) was an American composer of opera, songs and instrumental and chamber music, as well as a cellist, organist and pianist.
Relevant evidence: No