Ménard C., Bon F., Dessie A., Bruxelles L., Douze K., Fauvelle F.-X., Khalidi L., Lesur J., Mensan R. 2014, Late Stone Age variability in the Main Ethiopian Rift: New data from the Bulbula River, Ziway-Shala basin, Quaternary International
http://dx.doi.org/10.1016/j.quaint.2014.07.019