. "Collection of biographical materials, notebooks, teaching documents; correspondence documenting Klein's friendships with Darius Milhaud, Giacinto Scelsi, Ernst Toch, and Fritz Reiner; theory studies; holograph and ms. scores and sketches; sound discs of Jean Kuhns playing \"Regenzeit,\" and \"Variations on Star-spangled banner for 2 pianos\"; and a cassette tape of an interview with his son, Gerhard Klein, Sept. 3, 1987."@en . "Interviews"@en . . . . . . . . . . . . . . . . "Class notes"@en . . . . . . . . . "Walther Klein papers"@en . . .