Topeka — Gov. Sam Brownback on Wednesday will participate in a ceremony commemorating the 50th anniversary of the March on Washington and Martin Luther King's "I Have a Dream" speech. The ceremony at the Brown v. Board of Education National Historic Site is being held in conjunction with events taking place across the country. The King Center invited Brownback to celebrate with the ceremonial ringing of a bell at 2 p.m. The event starts at 1:30 p.m.