Iannis Xenakis (1922-2000) was one of the great composers of the late 20th Century. This now out-of-print book from 1986 is one of the most important resources on Xenakis in English.
It is a biography, but the focus is on his music and architecture, not his personal life. For me, the most valuable part of the book is the extensive coverage of his participation and leadership in the Resistance from 1941-1945 (19-30). This heroic movement against foreign occupation and fascism culminated in tragegy when the British demanded the surrrender of the Communist-led forces, which according to Xenakis had the support of 70% of the population, and the EAM and ELAS capitulated, leading to right-wing rule in Greece until the generals were removed from power in 1974. There is a great photo of Xenakis in Athens in 1974 upon his long-delayed return from a 27-year exile (229). The book includes several other black-and-white photos and drawings, including Xenakis with his wife and daughter (231), Xenakis at Persepolis in Iran (217), and Xenakis in the front row of a march in Athens on March 25, 1942 protesting the German occupation (21).
This may be the single best book on Xenakis in English, but Harley's is the most comprehensive on Xenakis's music, Conversations With Iannis Xenakis makes great reading, and then there is Xenakis's own Formalized Music: Thought and Mathematics in Composition (Harmonologia Series, No 6), which is of course indispensable.
Matossian does a good job of presenting context for understanding Xenakis's music, while lacking the ability to go into as much depth into the theory and construction of the compositions as Harley or Xenakis himself.
(verified library loan)