Caption President Barack Obama will deliver the keynote address and Aretha Franklin will headline the entertainers at this weekend's dedication of the Martin Luther King Jr. Memorial on the National Mall. The dedication was postponed from late August because of Hurricane Irene. Journalist Roland Martin will be the emcee. Besides Obama, speakers will include civil rights leaders Julian Bond, Rep. John Lewis, the Rev. Jesse Jackson and members of the King family. Journalist Dan Rather will also speak. A ceremonial dedication will be held at 11 A.M. on the grounds of the memorial, where the “Queen of Soul” will perform. The towering 30-foot monument is the first dedicated to a black leader on the National Mall. King stands with his arms crossed, carved from a stone and looking toward the horizon.