AP File Photo-In this July 2, 1964 file photo, President Lyndon Johnson signs the Civil Rights Act in the East Room of the White House in Washington. Standing from left, are Sen. Everett Dirksen, R-Ill.; Rep. Clarence Brown, R-Ohio; Sen. Hubert Humphrey, D-Minn.; Rep. Charles Halleck, R-Ind.; Rep. William McCullough, R-Ohio; and Rep. Emanuel Celler, D-N.Y. The Lyndon Baines Johnson Presidential Library in Austin is hosting a civil rights summit this week, highlighted by a keynote address by President Barack Obama. The library is holding the three-day conference to commemorate the 50th anniversary of the 1964 Civil Rights Act signed into law by Johnson.