The fourth female British act in history to have her first album debut at number one makes a guest appearance on the 29th studio album by what artist?
Lay It Down (Al Green album): Lay It Down is the 29th studio album by American recording artist Al Green, released May 27, 2008, on Blue Note Records. Lay It Down (Al Green album):  Four tracks feature guest artists, two with Anthony Hamilton, and one each with John Legend and Corinne Bailey Rae. Corinne Bailey Rae:  She released her debut album, "Corinne Bailey Rae", in February 2006, and became the fourth female British act in history to have her first album debut at number one.
Al Green