U.S. President Barack Obama, left, stands for a moment of silence for Nelson Mandela during an official dinner with South African President Jacob Zuma at the Presidential Guest House on Saturday, June... more 
U.S. President Barack Obama, left, stands for a moment of silence for Nelson Mandela during an official dinner with South African President Jacob Zuma at the Presidential Guest House on Saturday, June 29, 2013, in Pretoria, South Africa. The visit comes at a poignant time, with former South African president and anti-apartheid hero Nelson Mandela ailing in a Johannesburg hospital. (AP Photo/Evan Vucci) less 
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Associated Press | Photo By Evan Vucci
Sun, Jun 30, 2013 4:15 AM EDT