sentences:  His final concerts were three performances of the "Requiem" of Wolfgang Amadeus Mozart in the summer of 1982 with the Masterworks Chorale and the Midsummer Mozart Festival Orchestra.The short story "Addio San Francisco", which appears in the anthology "Murder at the Opera" (Mysterious Press, 1989), was written by Simmons with editor Thomas Godfrey, under a pseudonym.Simmons died in a canoeing accident at age 32 near Lake Placid in New York.