The Prokofiev piano sonata with the "Precipitato" movement (3rd) is Sonata #7 in B-Flat, Op. 83. I heard it performed just the other day by the exciting young Canadian pianist, Stewart Goodyear. There's a famous Horowitz recording, and Richter, of course. The more recent sonata set by the Finnish pianist Matti Raekallio on Ondine is excellent. Art Scott Livermore, Cal.