American singer Oliver Tree among list of passengers in deadly Brazil helicopter crash NBC NewsSinger Oliver Tree Is Said to Have Died in Collision of Helicopters in Brazil The New York TimesOliver Tree, "Life Goes On" and "Miss You" Singer, Dies in Helicopter Crash at 32 The Hollywood ReporterSinger Oliver Tree, 32, Among 6 Killed in Fiery Crash Involving Two Helicopters While on World Tour People.com
