Piece No. 4a, four-layer version, audio, 1994 (30:00 x 4). Layer 1. Layers (parts) can sound together or separately. - Sergey Zagny, piano. Theremin Center, Moscow, 09 07 1993 - Zagny Edition.Piece No. 4a, four-layer version, audio, 1994 (30:00 x 4). Layer 1. Layers (movements) may sound together or separately.– Sergei Zagny, piano. Theremin Center, Moscow, 7.09.1993. - Zagny Edition.