2. Temporal flow chart for Herma indicating changes in musical parameters, perceived high-level temporal gestalts, and different pitch sets articulated over the course of the work. The dynamic curve is multiple valued where multiple dynamics are marked simultaneously. Times are taken from Yuji Takahashi's Denon recording (Iannis Xenakis, Herma, Yuji Takahashi, piano. Denon 33CO-1052 [1972]. Compact disc.)
Robert A. Wannamaker, Structure and Perception in Herma by Iannis Xenakis, Music Theory Online 7.3 (May 2001)