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📜 Chase, Stephen Timothy. 2006. “Improvised Experimental Music and the Construction of a Collaborative Aesthetic.” PhD diss., University of Sheffield.
https://etheses.whiterose.ac.uk/14904/1/440929.pdf
Only a few of these 188 pages will relate to game in any capacity, either as a metaphor or in reference to Nyman. The main focus is titular "IEM", which is an introduced name for "free improv", but two places might be of higher interest to music gamers: graphic score usage (here as an analytic tool, "noting down" heard music, like occasionally in education), and, especially, close observation of workshops by Eddie Prevost, where the method could be classified as based on "constellation games" (on-off).
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