Abdullah Abullah (left) and Ashraf Ghani, shown here on August 8, have been contesting the results of Afghanistan's runoff presidential election for months. They are expected to sign a power-sharing deal on Sunday. Wakil Kohsar/AFP/Getty Images hide caption

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Nicaragua's Contra rebels in 1990. The U.S. backed the Contras in the 1980s, which led to the ouster of the leftist Sandinista leadership. But the U.S. aid violated American law and contributed to the biggest scandal of President Reagan's administration. Michael Stravato/AP hide caption

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Pro-independence demonstrators shout slogans outside the Catalan parliament on Friday in Barcelona, Spain. The Catalan parliament has approved rules for a self-determination referendum — which would violate the Spanish constitution. David Ramos/Getty Images hide caption

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During the three-day lockdown, the government of Sierra Leone is sending teams of workers door-to-door to talk to people about how to protect themselves from Ebola. Anders Kelto/NPR hide caption

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Prime Minister Ahmet Davutoglu, center, poses with dozens of freed Turkish hostages at the Esenboga Airport in Ankara Saturday. The group was held by militants in northern Iraq for more than three months. Adem Altan/AFP/Getty Images hide caption

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Venetians celebrate during the Festa del Redentore in Venice. The festival began in 1576 when the Republic's Senate voted to build a church on the Giudecca Island to Christ the Redeemer to thank God for the city's deliverance from the Plague. Marco Di Lauro/Getty Images hide caption

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