Christine King Farris, sister of Martin Luther King Jr., speaks at the Let Freedom Ring ceremony at the Lincoln Memorial. AP
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Participants hold a U.S. flag while gathered at the National Mall in Washington, DC. Bloomberg
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President Obama gives a pat on the back to former US President Bill Clinton after speaking during the Let Freedom Ring Commemoration and Call to Action. AFP/Getty Images
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Historian Robert Booker, right, waits backstage with Kevin Collins, who is dressed in a large puppet of Dr. Martin Luther King, before speaking in Knoxville, Tenn. AP
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NBA basketball legend Bill Russell attends the gathering in Washington, DC. AFP/Getty Images
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Orchard Knob Elementary School fifth-grader Chantal Nizigiyimana holds an American flag on the steps of the New York Peace Monument at Point Park on Lookout Mountain, Tenn. AP
