prof. regina williams on the music of duke ellington. on "american artifacts, clothes for a look at the smithsonian efforts to preserve an exhibit of the jefferson bible. the 50th anniversary celebration of the freedom rides and 13 men and women, black and white, boarded two buses bound for new orleans -- their goal -- to integrate southern bus stops. get the complete we can schedule at c-span.org/history, or press the c-span alert button to get our schedules e-mailed directly to you >> -- directly to you. >> this weekend, authors on the gulf oil spill, wall street, the universe, america's largest slave revolt, india, and the middle east, plus a panel discussion on the book industry. also, the former ambassador to yemen on the u.s. but the counter-terrorism efforts in that country. and one of the most significant standards of the cold war era -- the berlin wall. look for the complete schedule at booktv.org, and get our schedules e-mail directly to you. >> the southern part of sudan will separate from the northern part of the country in j