Cuban President Raul Castro (R), Venezuelan President Nicolas Maduro (2nd-R), Venezuelan First lady Cilia Flores (3rd-L) and Bolivian Preident Evo Morales (L) attend a massive rally at Revolution Square in Havana in honor of late leader Fidel Castro. Castro -- who ruled from 1959 until an illness forced him to hand power to his brother Raul in 2006 -- died Friday at age 90. The cause of death has not been announced. / AFP / JUAN BARRETO (Photo credit should read JUAN BARRETO/AFP via Getty Images)
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AFP JUAN BARRETO

Ecuadorean President Rafael Correa (R), Cuban President Raul Castro (C) and Venezuela's President Nicolas Maduro, during a massive rally at Revolution Square in Havana in honor of late leader Fidel Castro. Castro -- who ruled from 1959 until an illness forced him to hand power to his brother Raul in 2006 -- died Friday at age 90. The cause of death has not been announced. / AFP / PEDRO PARDO (Photo credit should read PEDRO PARDO/AFP via Getty Images)
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AFP PEDRO PARDO

Ecuadorean President Rafael Correa (R), Nigaraguan President Daniel Ortega (3rd-R) and Cuban President Raul Castro (L) during a massive rally at Revolution Square in Havana in honor of late leader Fidel Castro. Castro -- who ruled from 1959 until an illness forced him to hand power to his brother Raul in 2006 -- died Friday at age 90. The cause of death has not been announced. / AFP / JUAN BARRETO (Photo credit should read JUAN BARRETO/AFP via Getty Images)
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AFP JUAN BARRETO

Cuban President Raul Castro (C-R) stands next to Greece's Prime Minister Alexis Tsipras (C-L) during a massive rally at Revolution Square in Havana in honor of late leader Fidel Castro. Castro -- who ruled from 1959 until an illness forced him to hand power to his brother Raul in 2006 -- died Friday at age 90. The cause of death has not been announced. / AFP / JUAN BARRETO (Photo credit should read JUAN BARRETO/AFP via Getty Images)
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AFP JUAN BARRETO

People participate in a massive rally at Revolution Square in Havana in honor of late leader Fidel Castro. Castro -- who ruled from 1959 until an illness forced him to hand power to his brother Raul in 2006 -- died Friday at age 90. The cause of death has not been announced. / AFP / RODRIGO ARANGUA (Photo credit should read RODRIGO ARANGUA/AFP via Getty Images)
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AFP RODRIGO ARANGUA