Question: Who was mentor to the man whose works, along with those of Alban Berg, were included in the studio album entitled At the Grave of Richard Wagner?
Sentence (from "Anton Webern"): Along with his mentor Arnold Schoenberg and his colleague Alban Berg, Webern was at the core among those within and more peripheral to the circle of the Second Viennese School, including Ernst Krenek and Theodor W. Adorno.
Relevant evidence: Yes