Walter Raunig, Steffen Wenig (2005). Afrikas Horn. Otto Harrassowitz Verlag. p. 439. ISBN978-3447051750. Archived from the original on 14 September 2014. Retrieved 7 September 2014.
Walter Raunig, Steffen Wenig (2005). Afrikas Horn. Otto Harrassowitz Verlag. p. 439. ISBN978-3447051750. Archived from the original on 14 September 2014. Retrieved 7 September 2014.