1. Anderson, Julian: 1996, in A. Beyer (ed.), Perception and Deception, pp. 147–166.
2. Bak, Thor A.: 2002, in Jensen, Hansen and Nielsen (eds.), Per Nørgårds uendelighed-srœkke (Per Nørgård’s Infinity Series), pp. 207–216.
3. Beyer, Anders (ed.): 1996, The Music of Per Nørgård, Scolar Press.
4. Cage, John: 1961, Silence, Wesleyan University Press.
5. Carlsen, Jan Pilgaard: 1999, Rum i Pelle Gudmundsen-Holmgreen: Udstillingsbilleder (1968) med György Ligeti: Monument (1976) og Steve Reich: Piano Phase (1967) som indforende eksempler (Space in Pelle Gudmundsen-Holmgreen: Pictures at an Exhibition (1968) with György Ligeti: Monument (1976) and Steve Reich: Piano Phase (1967) as Introductory Examples), manuscript, Copenhagen University.