Karel Goeyvaerts was a Belgian composer. After studies at the Royal Flemish Music Conservatory in Antwerp, he studied composition in Paris with Darius Milhaud and analysis with Olivier Messiaen. He also studied ondes martenot with Maurice Martenot, who invented the instrument. In 1951, Goeyvaerts attended the famous Darmstadt New Music Summer School where he met Karlheinz Stockhausen who was five years younger. Wikipedia
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