Waters, Alan Rufus Economic centralization and the rigidity of tribal boundaries in Africa Alan Rufus Waters - Philadelphia : African Studies Association, 1972 - 19p. - Paper No.158 - 188 are all bound in one book; 181 . Subjects--Topical Terms: Boundaries, tribaltribalAfrica LC Class. No.: EAF QTO DT19.9.U57A35 No.181