1. Amimo, J.O., Wakhungu, J.W., Inyangala, B.O. and Mosi, R.O., 2007. The effects of non-genetic factors and estimation of genetic and phenotypic parameters and trends for milk yield in Ayrshire cattle in Kenya. Livestock Research for Rural Development, 19: 1
2. Bormann, J.M. and Wilson, D.E., 2010. Calving day and age at first calving in Angus heifers. Journal of Animal Science, 88, 1946–1957
3. Hatungumukana, G., Sidikou, D.I., Leroy, P. and Detilleux, J., 2007. Effects of non-genetic and crossbreeding factors on daily milk yield of Aryshire× (Sahiwal × Ankole) cows in Mahwa station (Burundi). International Journal of Livestock Science, 110 (1), 111–117
4. Hayhurst, C., Bradley, A., Forbes, A.B. and Royal, M.D., 2010. Genetic and non-genetic factors influencing Ostertagia ostertagi antibodies in UK Holstein-Friesian cattle. Journal of Dairy Science, 93(5), 2239–2243.
5. Missanjo, E.M., 2010. Genetic and phenotypic evaluation of Zimbabwean Jersey cattle towards the development of a selection index (unpublished MSc thesis, University of Zimbabwe)