Reinvestigation of Kuumbi cave, Zanzibar, reveals later stone age coastal habitation, early Holocene abandonment and iron age reoccupation nork Shipton, C, Crowther, A, Kourampas, N, Prendergast, M, Horton, M, Douka, K, Schwenninger, J, Faulkner, P, Quintana Morales, E, Langley, M, Tibesasa, R, Picornell-Gelabert, L, Wilmsen, E, Doherty, C, Veall, M, Ali, A, Petraglia, M, Boivin, N