Question: John Fonville has premiered works by composers including Ben Johnston, called, "one of the best non-famous composers this country has to offer" in 1990, by what American critic?
Sentence (from "Ben Johnston (composer)"): Benjamin Burwell Johnston, Jr. (born March 15, 1926 in Macon, Georgia) is a composer of contemporary music in just intonation: "one of the foremost composers of microtonal music" .
Relevant evidence: No