Curtin, Philip D. Economic change in precolonial Africa : Senegambia in the era of the slave trade / Philip D. Curtin - Madison : Wisconsin University Press , 1975 - xxix, 363p. : ill, ; 24 cm. Includes bibliographical references and index. Subjects--Topical Terms: Economic history--AfricaSlavery Dewey Class. No.: 330.9 / Af CUR