Art and power in the Central African Savanna : Luba, Songye, Chokwe, Luluwa : [published to accompany "Art and power in the Central African Savanna: Luba, Songye, Chokwe, Luluwa", an exhibition organized by the Cleveland Museum of Art to be held at the Menil Collection, Houston, 26 September 2008-4 January 2009, the Cleveland Museum of Art, 1 March - 7 June 2009, and the de Young Museum, Fine Arts Museums of San Francisco, 27 June - 11 October 2009]