1. Arthur, G. H. (1964).Wright's Veterinary Obstetrics, 3rd ed. Baillière, Tindall and Cox, London.
2. Dawson, F. L. M. (1958). Observations on the corpora albicantia in the ovaries of normal and infertile dairy cows.Journal of Agricultural Science,50, 322–330.
3. de St Croix, F. W. (1945).The Fulani of Northern Nigeria. Government Printer, Lagos.
4. Hopen, C. E. (1958).The Pastoral Fulbe Family in Gwandu. International African Institute, Oxford University Press.
5. Mason, I. L. (1951).The Classification of West African Livestock. Commonwealth Agricultural Bureaux.