Cornell and Cooper collaborated on Cooper's The Last Temptation album in '94. The two co-wrote a pair of songs, "Stolen Prayer" and "Unholy War," with Cornell providing vocals for each.
In his statement, Cooper said Cornell was referred to as "'The Voice' because he had the best voice in rock and roll."
"I was lucky enough to write and record two songs with him," the statement continued. "His death comes as a total shock to all of us. 'Black Hole Sun' will live on as a classic, and his is a true legacy of rock and roll."
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