1. An introduction to animal husbandry in the tropics;Williamson;Tropical series in Agriculture, Longman, London, Great Britain,1978
2. Enhanced reproduction in camels (Camelus dromedarius);Yagil;Comp Biochem Physiol,1984
3. The camel in today's world;Yagil;Bonn,1994
4. Reproductive physiology of the male;Tibary,1997
5. Reproductive disorders in the male camelid;Tibary,2000