Sahel: A semiarid region of north-central Africa south of the Sahara desert that stretches across six countries from Senegal to Chad.
Steppe: a biome (or subdivision of the Earth’s surface) that is composed of a swathe of temperate grassland stretching from Romania to China. Natural grassland with low rainfall.
Newby, J.E. (1978) The Ecological Resources of the Ouadi Rimé-Ouadi Achim Faunal Reserve, Chad (unpublished update to 1974 report).Direction des Parcs Nationaux, N'Djaména.
Spevak, E., Gilbert, T., Engel, H., Correll, T. and Houston, B. (2006) Returning the addax and the oryx to Tunisia. Communiqué, American Zoo and Aquarium Association, 2006: 13 - 14.